List 8

genetics

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  1. homeotic gene

    one the genes that are involved in embryologic development
    HLA stands for "human leukocyte antigen" click this icon to hear the preceding term pronounced.

    homeotic gene click this icon to hear the preceding term pronounced

    see regulator gene.

    homologous chromosomes click this icon to hear the preceding term pronounced

    chromosomes that are paired during the production of of sex cells in meiosis.

  2. recessive allele

    an allele that produces its characteristic phenotype only when its paired allele is identical
    Cystic fibrosis occurs as a result of inheriting a
    recessive allele for it from both parents.
  3. dominant allele

    an allele that produces the same phenotype whether its paired allele is identical or different
    The gene or genes for diabetes are incompletely penetrant.

    dominant allele

    an allele that masks the presence of a recessive allele in the phenotype.

  4. sex cell

    a spermatozoon or an ovum
    Humans have 46 chromosomes in each somatic cell and 23 in each
    sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which two different alleles for a trait are expressed unblended in the phenotype of heterozygous individuals.

  5. allele

    any of the forms of a gene that can occupy the same locus
    Neither
    allele is dominant or recessive, so that both appear in the phenotype or influence it.
  6. polygenic

    of or relating to an inheritable character that is controlled by several genes at once; of or related to or determined by polygenes
    The collective group of symptoms known as sickle-cell trait is an example.

    polygenic trait click this icon to hear the preceding term pronounced

    an inherited trait that is determined by genes at two or more loci.

  7. phenotype

    observable characteristics produced by genes and environment
    Since the gene for albinism is recessive, it only shows up in the
    phenotype of homozygous recessive people.
  8. regulator gene

    a gene that produces a repressor substance that inhibits an operator gene
    HLA stands for "human leukocyte antigen" click this icon to hear the preceding term pronounced.

    homeotic gene click this icon to hear the preceding term pronounced

    see
    regulator gene.

    homologous chromosomes click this icon to hear the preceding term pronounced

    chromosomes that are paired during the production of of sex cells in meiosis.

  9. monozygotic

    derived from a single fertilized egg
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be explained by simple rules of dominance and recessiveness of genes.

    modifying gene

    a gene that can alter the expression of another gene in the phenotype of an individual.

    monozygotic twins click this icon to hear the preceding term pronounced

    identical twins.

  10. genotype

    the alleles at specified loci present in an organism
    More precisely, it is the collective
    genotype of a population.

    genes click this icon to hear the preceding term pronounced

    units of inheritance usually occurring at specific locations, or loci, on a chromosome.

  11. proteome

    the full complement of proteins produced by a particular genome
    This decoding of the human
    proteome will be an even more daunting task than the original Human Genome Project.
  12. homozygous

    having identical alleles at corresponding chromosomal loci
    Since the gene for albinism is recessive, it only shows up in the phenotype of
    homozygous recessive people.
  13. X-linked

    relating to genes or characteristics or conditions carried on the X chromosome
    Since it is an
    X-linked trait, males more often have it expressed in their phenotypes.
  14. somatic cell

    a cell that does not participate in reproduction
    Humans have 46 chromosomes in each
    somatic cell and 23 in each sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which two different alleles for a trait are expressed unblended in the phenotype of heterozygous individuals.

  15. meiosis

    cell division in sexually reproducing organisms
    HLA stands for "human leukocyte antigen" click this icon to hear the preceding term pronounced.

    homeotic gene click this icon to hear the preceding term pronounced

    see regulator gene.

    homologous chromosomes click this icon to hear the preceding term pronounced

    chromosomes that are paired during the production of of sex cells in
    meiosis.

  16. type AB

    the blood group whose red cells carry both the A and B antigens
    Type AB blood is an example.
  17. myotonic

    of or relating to or caused by myotonia
    The
    myotonic form of muscular dystrophy is an example.
  18. Gregor Mendel

    Augustinian monk and botanist whose experiments in breeding garden peas led to his eventual recognition as founder of the science of genetics (1822-1884)
    Through his plant cross-breeding experiments,
    Gregor Mendel proved that this was wrong

    Back to Top

    - C -

    carrier

    an individual who is heterozygous for a trait that only shows up in the phenotype of those who are homozygous recessive.

  19. sex-limited

    relating to characteristics that are expressed differently in the two sexes
    See
    sex-limited gene.

    sex-limited gene

    a gene that can be inherited by both genders but is usually expressed in only males or females.

  20. centromere

    a specialized condensed region of each chromosome that appears during mitosis where the chromatids are held together to form an X shape
    Such chromosomes are alike with regard to size and also position of the
    centromere.
  21. heterozygous

    having dissimilar alleles at corresponding chromosomal loci
    Through his plant cross-breeding experiments, Gregor Mendel proved that this was wrong

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    - C -

    carrier

    an individual who is
    heterozygous for a trait that only shows up in the phenotype of those who are homozygous recessive.

  22. metabolic disorder

    a disorder or defect of metabolism
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    - D -

    diabetes click this icon to hear the preceding term pronounced

    an inherited
    metabolic disorder in which there are abnormally high blood sugar levels.

  23. recessive

    of or pertaining to a recession
    Since the gene for albinism is
    recessive, it only shows up in the phenotype of homozygous
    recessive people.
  24. homozygote

    (genetics) an organism having two identical alleles of a particular gene and so breeding true for the particular characteristic
    Individuals who are homozygous for a trait are referred to as
    homozygotes.
  25. icon

    a visual representation produced on a surface
    albinism click this
    icon to hear the preceding term pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  26. gamete

    a mature sexual reproductive cell
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    - N -

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    - O -

    ovum click this icon to hear the preceding term pronounced (plural ova click this icon to hear the preceding term pronounced)

    a female sex cell or
    gamete.

  27. clotting factor

    any of the factors in the blood whose actions are essential for blood coagulation
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    - H -

    hemophilia click this icon to hear the preceding term pronounced

    an X-linked genetically inherited recessive disease in which one or more of the normal blood
    clotting factors is not produced.

  28. codon

    a specific sequence of three adjacent nucleotides on a strand of DNA or RNA that specifies the genetic code information for synthesizing a particular amino acid
    The initial stage of discovering all human DNA
    codons was completed early in 2001 at a cost of 2.7 billion dollars.
  29. amino acid

    organic compounds containing an amino group and acid group
    However, because they are different, their action may result in different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that are the components of proteins.

  30. Human Genome Project

    an international study of the entire human genetic material
    See
    Human Genome Project.

    genome imprinting click this icon to hear the preceding term pronounced

    an inheritance pattern in which a gene will have a different effect depending on the gender of the parent from whom it is inherited.

  31. chromosome

    a threadlike strand of DNA that carries genes
    The alleles for a trait occupy the same locus or position on homologous
    chromosomes and thus govern the same trait.
  32. inherited disease

    a disease or disorder that is inherited genetically
    Usually, the term is used in reference to the crossing of two pure breeding (homozygous) plants.

    cystic fibrosis click this icon to hear the preceding term pronounced

    a genetically
    inherited disease in children that results in chronic fluid development in the lungs, making breathing difficult.

  33. precede

    be earlier in time
    albinism click this icon to hear the
    preceding term pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  34. fraternal twin

    one of two twins who developed from separate fertilized eggs
    Fraternal twins may look similar but are not genetically identical.

    multiple-allele series click this icon to hear the preceding term pronounced

    a situation in which a gene has more than two alleles.

  35. leukocyte

    blood cells that engulf and digest bacteria and fungi
    HLA stands for "human
    leukocyte antigen" click this icon to hear the preceding term pronounced.

    homeotic gene click this icon to hear the preceding term pronounced

    see regulator gene.

    homologous chromosomes click this icon to hear the preceding term pronounced

    chromosomes that are paired during the production of of sex cells in meiosis.

  36. daughter cell

    a cell formed by the division or budding of another cell
    Meiosis involves two divisions and results in four
    daughter cells, each containing only half the original number of chromosomes--23 in the case of humans.
  37. gene

    part of DNA controlling physical characteristics and growth
    Since the
    gene for albinism is recessive, it only shows up in the phenotype of homozygous recessive people.
  38. purebred

    bred for many generations from member of a recognized breed or strain
    This disease is also called Huntington's chorea click this icon to hear the preceding term pronounced.

    hybrids click this icon to hear the preceding term pronounced

    offspring that are the result of mating between two genetically different kinds of parents--the opposite of
    purebred.

  39. Tay-Sachs

    a hereditary disorder of lipid metabolism occurring most frequently in individuals of Jewish descent in eastern Europe; accumulation of lipids in nervous tissue results in death in early childhood
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    - T -

    Tay-Sachs Disease click this icon to hear the preceding term pronounced

    a genetically inherited condition caused by the inability to produce the enzyme hexosaminidase A. This results in progressively increased fluid pressure on the brain and the subsequent degeneration of the brain and nervous system beginning about 6 months of age and inevitably resulting in death usually by age 2-3.

  40. sex chromosome

    a chromosome that determines the sex of an individual
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    - W -

    Back to Top

    - X -

    X-linked

    referring to a gene that is carried by an X
    sex chromosome.

  41. skeletal muscle

    a muscle that is connected at either or both ends to a bone and so move parts of the skeleton; a muscle that is characterized by transverse stripes
    MD is characterized by a gradual, irreversible wasting of
    skeletal muscle.
  42. genetically

    by genetic mechanisms
    albinism click this icon to hear the preceding term pronounced

    the
    genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  43. lense

    a transparent optical device used to converge or diverge transmitted light and to form images
    This is the case with hemophilia.

    cataract click this icon to hear the preceding term pronounced

    an impairment of vision caused by the
    lenses of the eyes becoming cloudy.

  44. reproductive cell

    a spermatozoon or an ovum
    These modified particles were thought to migrate via blood to the
    reproductive cells and subsequently could be inherited by the next generation.
  45. zygote

    the cell from the union of a haploid spermatozoon and ovum
    Twins that come from the same
    zygote are essentially the same genetically.
  46. inactivation

    the process of rendering inactive
    Angelman syndrome click this icon to hear the preceding term pronounced

    a rare genetically inherited form of mental retardation due to the deletion or
    inactivation of specific genes on chromosome 15.

  47. Huntington's chorea

    hereditary disease
    This disease is also called
    Huntington's chorea click this icon to hear the preceding term pronounced.

    hybrids click this icon to hear the preceding term pronounced

    offspring that are the result of mating between two genetically different kinds of parents--the opposite of purebred.

  48. imprinting

    a learning process in early life whereby species specific patterns of behavior are established
    The inheritance of this syndrome is subject to genome
    imprinting.
  49. sex-linked

    concerning characteristics that are determined by genes carried on the sex chromosomes (on the X chromosome in particular)
    It is a
    sex-linked trait most often passed on to sons by their mothers.
  50. hemophilia

    congenital tendency to uncontrolled bleeding
    This is the case with
    hemophilia.

    cataract click this icon to hear the preceding term pronounced

    an impairment of vision caused by the lenses of the eyes becoming cloudy.

  51. pronounce

    speak or utter in a certain way
    albinism click this icon to hear the preceding term
    pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  52. red blood cell

    a mature blood cell that contains hemoglobin to carry oxygen to the bodily tissues; a biconcave disc that has no nucleus
    See sex-controlled gene.

    sickle-cell trait

    a genetically inherited recessive condition in which
    red blood cells are distorted resulting in severe anemia and related symptoms that are often fatal in childhood.

  53. amino

    pertaining to or containing any of a group of organic compounds of nitrogen derived from ammonia
    However, because they are different, their action may result in different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that are the components of proteins.

  54. trait

    a distinguishing feature of your personal nature
    An individual with these
    traits is an "albino."
  55. cystic fibrosis

    the most common congenital disease
    Usually, the term is used in reference to the crossing of two pure breeding (homozygous) plants.

    cystic fibrosis click this icon to hear the preceding term pronounced

    a genetically inherited disease in children that results in chronic fluid development in the lungs, making breathing difficult.

  56. unblended

    not blended or mixed together
    Humans have 46 chromosomes in each somatic cell and 23 in each sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which two different alleles for a trait are expressed
    unblended in the phenotype of heterozygous individuals.

  57. genome

    the full DNA sequence of an organism
    The inheritance of this syndrome is subject to
    genome imprinting.
  58. somatic

    characteristic of the body as opposed to the mind or spirit
    Humans have 46 chromosomes in each
    somatic cell and 23 in each sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which two different alleles for a trait are expressed unblended in the phenotype of heterozygous individuals.

  59. muscular dystrophy

    any of several hereditary diseases of the muscular system characterized by weakness and wasting of skeletal muscles
    It is believed that the lack of abundant sun exposure early in life is somehow responsible for the later onset of MS.

    muscular dystrophy click this icon to hear the preceding term pronounced (MD)

    any of a group of inherited progressive muscle disorders caused by a defect in one or more genes that control muscle function.

  60. deoxyribonucleic acid

    (biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information
    DNA click this icon to hear the preceding term pronounced (
    deoxyribonucleic acid click this icon to hear the preceding term pronounced)

    a large organic molecule that stores the genetic code for the synthesis of proteins.

  61. urate

    a salt of uric acid
    See phenotype.

    gout click this icon to hear the preceding term pronounced

    a genetically inherited metabolic disorder in which there is an imbalance of uric acid in the blood which causes a build up of
    urates in joint areas.

  62. albinism

    the absence of pigmentation in the eyes, skin, and hair
    albinism click this icon to hear the preceding term pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  63. hemophiliac

    someone who has hemophilia and is subject to uncontrollable bleeding
    Swollen joints caused by internal bleeding is a common problem for
    hemophiliacs.
  64. click

    a short light metallic sound
    albinism
    click this icon to hear the preceding term pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  65. fibrosis

    development of excess fibrous connective tissue in an organ
    Usually, the term is used in reference to the crossing of two pure breeding (homozygous) plants.

    cystic
    fibrosis click this icon to hear the preceding term pronounced

    a genetically inherited disease in children that results in chronic fluid development in the lungs, making breathing difficult.

  66. learning disability

    a disorder found in children of normal intelligence who have difficulties in learning specific skills
    Most fragile-X males have large testes, big ears, narrow faces, and sensory integration dysfunctions that result in
    learning disabilities.
  67. dystrophy

    any of several hereditary diseases of the muscular system characterized by weakness and wasting of skeletal muscles
    It is believed that the lack of abundant sun exposure early in life is somehow responsible for the later onset of MS.

    muscular
    dystrophy click this icon to hear the preceding term pronounced (MD)

    any of a group of inherited progressive muscle disorders caused by a defect in one or more genes that control muscle function.

  68. Huntington's disease

    hereditary disease
    Huntington's disease

    a severe genetically inherited fatal degenerative nerve disorder.

  69. inherit

    receive from a predecessor
    albinism click this icon to hear the preceding term pronounced

    the genetically
    inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  70. mental retardation

    lack of normal development of intellectual capacities
    Angelman syndrome click this icon to hear the preceding term pronounced

    a rare genetically inherited form of
    mental retardation due to the deletion or inactivation of specific genes on chromosome 15.

  71. sickle-cell anemia

    a congenital form of anemia occurring mostly in blacks
    Sickle-cell trait is also known as
    sickle-cell anemia.

    somatic cell click this icon to hear the preceding term pronounced

    any cell in the body except those directly involved with reproduction.

  72. cystic

    of or relating to a normal cyst
    Usually, the term is used in reference to the crossing of two pure breeding (homozygous) plants.

    cystic fibrosis click this icon to hear the preceding term pronounced

    a genetically inherited disease in children that results in chronic fluid development in the lungs, making breathing difficult.

  73. blood clotting

    a process in which liquid blood is changed into a semisolid mass (a blood clot)
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    - H -

    hemophilia click this icon to hear the preceding term pronounced

    an X-linked genetically inherited recessive disease in which one or more of the normal
    blood clotting factors is not produced.

  74. Mendelian

    of or relating to Gregor Mendel or in accord with Mendel's laws
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be explained by simple rules of dominance and recessiveness of genes.

    modifying gene

    a gene that can alter the expression of another gene in the phenotype of an individual.

    monozygotic twins click this icon to hear the preceding term pronounced

    identical twins.

  75. locus

    the scene of any event or action
    The alleles for a trait occupy the same
    locus or position on homologous chromosomes and thus govern the same trait.
  76. cell division

    the process in reproduction and growth by which a cell divides to form daughter cells
    They are visible only under magnification during certain stages of
    cell division.
  77. genetic

    relating to the study of heredity and variation in organisms
    DNA click this icon to hear the preceding term pronounced (deoxyribonucleic acid click this icon to hear the preceding term pronounced)

    a large organic molecule that stores the
    genetic code for the synthesis of proteins.

  78. decode

    convert code into ordinary language
    Research to
    decode the human genome began in earnest in 1986, funded by the U.S.
  79. blood type

    human blood cells that have the same antigens
    The ABO
    blood type system is an example.
  80. homologous

    similar in position, structure, function, or characteristics
    The alleles for a trait occupy the same locus or position on
    homologous chromosomes and thus govern the same trait.
  81. mitosis

    the process by which a cell divides into two smaller cells
    They reproduce by
    mitosis.
  82. preceding

    existing or coming before
    albinism click this icon to hear the
    preceding term pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  83. ovum

    the female reproductive cell; the female gamete
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    - J -

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    - K -

    Back to Top

    - L -

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    - M -

    meiosis click this icon to hear the preceding term pronounced

    cell division in specialized tissues of ovaries and testes which results in the production of sperm or
    ova.

  84. double helix

    a pair of parallel helices intertwined about a common axis
    DNA is composed of sugars, phosphates and bases arranged in a
    double helix shaped molecular structure.
  85. pronounced

    strongly marked; easily noticeable
    albinism click this icon to hear the preceding term
    pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  86. X chromosome

    the sex chromosome that is present in both sexes: singly in males and doubly in females
    The next and subsequent generations are referred to as f2, f3, etc.

    fragile-X syndrome click this icon to hear the preceding term pronounced

    a relatively common genetically inherited abnormality of the
    X chromosome which results in mental retardation.

  87. blood cell

    either of two types of cells (erythrocytes and leukocytes) and sometimes including platelets
    See sex-controlled gene.

    sickle-cell trait

    a genetically inherited recessive condition in which red
    blood cells are distorted resulting in severe anemia and related symptoms that are often fatal in childhood.

  88. body part

    any part of an organism such as an organ or extremity
    Shortly after conception, regulator genes work as master switches orchestrating the timely development of our
    body parts.
  89. identical twin

    either of two twins developed from the same fertilized ovum
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be explained by simple rules of dominance and recessiveness of genes.

    modifying gene

    a gene that can alter the expression of another gene in the phenotype of an individual.

    monozygotic twins click this icon to hear the preceding term pronounced

    identical twins.

  90. protein

    an organic compound essential to living cells
    However, because they are different, their action may result in different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that are the components of
    proteins.

  91. stutter

    speak haltingly
    See sex cell.

    sperm click this icon to hear the preceding term pronounced

    a male sex cell or gamete.

    stuttering alleles

    defective alleles that have segments which are doubled in their transmission from generation to generation.

  92. molecule

    the simplest structural unit of an element or compound
    However, because they are different, their action may result in different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small
    molecules that are the components of proteins.

  93. incompletely

    not to a full degree or extent
    The gene or genes for diabetes are
    incompletely penetrant.

    dominant allele

    an allele that masks the presence of a recessive allele in the phenotype.

  94. genetics

    the study of heredity and variation in organisms
    In large populations, random deviations in allele frequencies in one direction are more likely to be cancelled out by random changes in the opposite direction.

    genetics click this icon to hear the preceding term pronounced

    the study of gene structure and action and the patterns of inheritance of traits from parent to offspring.

  95. anemia

    a deficiency of red blood cells
    See sex-controlled gene.

    sickle-cell trait

    a genetically inherited recessive condition in which red blood cells are distorted resulting in severe
    anemia and related symptoms that are often fatal in childhood.

  96. descendent

    a person considered as descended from some ancestor or race
    It has been most common among the
    descendents of Eastern European Jews (Ashkenazi Jews).

    true breeding

    see purebred.

  97. cross-pollination

    fertilization by transfer of pollen from the anthers of one flower to the stigma of another
    Such traits are said to be codominant.

    cross-pollination

    the mating of two genetically different plants of the same species.

  98. detectable

    capable of being discovered
    This was a variation of Lamarck's incorrect idea of the "inheritance of acquired characteristics."

    phenotype click this icon to hear the preceding term pronounced

    the observable or
    detectable characteristics of an individual organism--the
    detectable expression of a genotype.

    pleiotropy click this icon to hear the preceding term pronounced

    the situation in which a single gene is responsible for a variety of traits.

  99. testis

    one of the two male reproductive glands that produce spermatozoa and secrete androgens
    Most fragile-X males have large
    testes, big ears, narrow faces, and sensory integration dysfunctions that result in learning disabilities.
  100. cancel out

    wipe out the effect of something
    In large populations, random deviations in allele frequencies in one direction are more likely to be
    cancelled out by random changes in the opposite direction.

    genetics click this icon to hear the preceding term pronounced

    the study of gene structure and action and the patterns of inheritance of traits from parent to offspring.

  101. neuron

    a cell that is specialized to conduct nerve impulses
    MS occurs as a consequence of one's own immune system attacking the insulating sheath that normally protects
    neurons.
  102. inherited

    occurring among members of a family usually by heredity
    albinism click this icon to hear the preceding term pronounced

    the genetically
    inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  103. multicellular

    consisting of many basic structural and functional units
    Most cells in
    multicellular plants and animals are somatic cells.
  104. Ashkenazi

    a Jew of eastern European or German descent
    It has been most common among the descendents of Eastern European Jews (
    Ashkenazi Jews).

    true breeding

    see purebred.

  105. antigen

    any substance that stimulates an immune response in the body
    HLA stands for "human leukocyte
    antigen" click this icon to hear the preceding term pronounced.

    homeotic gene click this icon to hear the preceding term pronounced

    see regulator gene.

    homologous chromosomes click this icon to hear the preceding term pronounced

    chromosomes that are paired during the production of of sex cells in meiosis.

  106. deletion

    any process whereby sounds or words are left out of spoken words or phrases
    Angelman syndrome click this icon to hear the preceding term pronounced

    a rare genetically inherited form of mental retardation due to the
    deletion or inactivation of specific genes on chromosome 15.

  107. mutate

    undergo a change or alteration in form or qualities
    For instance, a trait that has only one allele (A) can
    mutate to a new form (a).
  108. genetic code

    the ordering of nucleotides in DNA molecules that carries the genetic information in living cells
    DNA click this icon to hear the preceding term pronounced (deoxyribonucleic acid click this icon to hear the preceding term pronounced)

    a large organic molecule that stores the
    genetic code for the synthesis of proteins.

  109. DNA

    a long linear polymer found in the nucleus of a cell
    Chromosomes are composed primarily of
    DNA and protein.
  110. full complement

    number needed to make up a whole force
    Proteins may be enzymes, hormones, antibodies, structural components, or gas-transporting molecules.

    proteome click this icon to hear the preceding term pronounced

    the
    full complement of proteins produced by an individual (or a species).

  111. sickle

    an edge tool for cutting grass or crops
    The collective group of symptoms known as
    sickle-cell trait is an example.

    polygenic trait click this icon to hear the preceding term pronounced

    an inherited trait that is determined by genes at two or more loci.

  112. term

    a limited period of time during which something lasts
    albinism click this icon to hear the preceding
    term pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  113. cell

    the basic structural and functional unit of all organisms
    In contrast, an acute disease is one with a rapid onset and a short but usually severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-carrying bodies in the nucleus of a
    cell.

  114. psoriasis

    a chronic skin disease characterized by dry red patches covered with scales; occurs especially on the scalp and ears and genitalia and the skin over bony prominences
    See Human Genome Project.

    psoriasis click this icon to hear the preceding term pronounced

    an inherited disease characterized by recurring thick, reddish patches of inflamed skin.

  115. orchestrate

    plan and direct (a complex undertaking)
    Shortly after conception, regulator genes work as master switches
    orchestrating the timely development of our body parts.
  116. metabolic

    of or relating to metabolism
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    - D -

    diabetes click this icon to hear the preceding term pronounced

    an inherited
    metabolic disorder in which there are abnormally high blood sugar levels.

  117. chorea

    any of several degenerative nervous disorders characterized by spasmodic movements of the body and limbs
    This disease is also called Huntington's
    chorea click this icon to hear the preceding term pronounced.

    hybrids click this icon to hear the preceding term pronounced

    offspring that are the result of mating between two genetically different kinds of parents--the opposite of purebred.

  118. helix

    a curve that lies on the surface of a cylinder or cone
    DNA is composed of sugars, phosphates and bases arranged in a double
    helix shaped molecular structure.
  119. hyperactive

    more engaged than normal
    Children with Angleman syndrome typically also have small heads, experience seizures, have pronounced speech impairment, are
    hyperactive, and have balance disorders.
  120. decoding

    the activity of making clear or converting from code into plain text
    This
    decoding of the human proteome will be an even more daunting task than the original Human Genome Project.
  121. kidney failure

    inability of the kidneys to excrete wastes and to help maintain the electrolyte balance
    In advanced stages, this often results in blindness from cataracts, nerve damage, gangrene in the feet and legs leading to amputation, heart disease, and
    kidney failure.
  122. graphical

    relating to or presented by a graph
    Punnett square click this icon to hear the preceding term pronounced

    a simple
    graphical method of showing all of the potential combinations of offspring genotypes that can occur and their probability given the parent genotypes.

  123. imprint

    mark or stamp with or as if with pressure
    The inheritance of this syndrome is subject to genome
    imprinting.
  124. pigmentation

    coloration of living tissues by pigment
    albinism click this icon to hear the preceding term pronounced

    the genetically inherited condition in which there is a marked deficiency of
    pigmentation in skin, hair, and eyes.

  125. pollination

    transfer of the fine spores that contain male gametes
    Such traits are said to be codominant.

    cross-
    pollination

    the mating of two genetically different plants of the same species.

  126. magnification

    the act of expanding something in apparent size
    They are visible only under
    magnification during certain stages of cell division.
  127. diabetes

    a disease characterized by high glucose levels in the blood
    They may be inherited or caused by
    diabetes and environmental factors.

    photo of a normal eye and another with a cataract

    chronic disease

    an illness that lasts for a long period of time or indefinitely.

  128. retardation

    the act of slowing down or falling behind
    Angelman syndrome click this icon to hear the preceding term pronounced

    a rare genetically inherited form of mental
    retardation due to the deletion or inactivation of specific genes on chromosome 15.

  129. impairment

    a reduction in quality or strength
    Children with Angleman syndrome typically also have small heads, experience seizures, have pronounced speech
    impairment, are hyperactive, and have balance disorders.
  130. syndrome

    a pattern of symptoms indicative of some disease
    Angelman
    syndrome click this icon to hear the preceding term pronounced

    a rare genetically inherited form of mental retardation due to the deletion or inactivation of specific genes on chromosome 15.

  131. enzyme

    a complex protein produced by cells that acts as a catalyst
    Proteins may be
    enzymes, hormones, antibodies, structural components, or gas-transporting molecules.

    proteome click this icon to hear the preceding term pronounced

    the full complement of proteins produced by an individual (or a species).

  132. sperm

    the male reproductive cell; the male gamete
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    meiosis click this icon to hear the preceding term pronounced

    cell division in specialized tissues of ovaries and testes which results in the production of
    sperm or ova.

  133. uric acid

    a white tasteless odorless crystalline product of protein metabolism; found in the blood and urine
    See phenotype.

    gout click this icon to hear the preceding term pronounced

    a genetically inherited metabolic disorder in which there is an imbalance of
    uric acid in the blood which causes a build up of urates in joint areas.

  134. regulator

    a device for controlling flow, pressure, temperature, etc.
    HLA stands for "human leukocyte antigen" click this icon to hear the preceding term pronounced.

    homeotic gene click this icon to hear the preceding term pronounced

    see
    regulator gene.

    homologous chromosomes click this icon to hear the preceding term pronounced

    chromosomes that are paired during the production of of sex cells in meiosis.

  135. clotting

    the process of forming semisolid lumps in a liquid
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    hemophilia click this icon to hear the preceding term pronounced

    an X-linked genetically inherited recessive disease in which one or more of the normal blood
    clotting factors is not produced.

  136. RNA

    (biochemistry) a long linear polymer of nucleotides found in the nucleus but mainly in the cytoplasm of a cell where it is associated with microsomes; it transmits genetic information from DNA to the cytoplasm and controls certain chemical processes in the cell
    Viruses are not cells but rather
    RNA or DNA molecules surrounded by a protein coating.
  137. mating

    the act of pairing a male and female for reproductive purposes
    Such traits are said to be codominant.

    cross-pollination

    the
    mating of two genetically different plants of the same species.

  138. antibody

    a protein that produces an immune response
    Proteins may be enzymes, hormones,
    antibodies, structural components, or gas-transporting molecules.

    proteome click this icon to hear the preceding term pronounced

    the full complement of proteins produced by an individual (or a species).

  139. symptom

    a sensation associated with a particular disease
    Symptoms include painfully inflamed joints, especially of the feet and hands, that can become chronic and result in deformity.
  140. central nervous system

    the portion of the vertebrate nervous system consisting of the brain and spinal cord
    Multiple-allele series only partly follow simple Mendelian genetics.

    multiple sclerosis click this icon to hear the preceding term pronounced (MS)

    a genetically inherited progressive disease of the
    central nervous system.

  141. also known as

    as known or named at another time or place
    Genome imprinting is
    also known as genetic imprinting.

    genotype click this icon to hear the preceding term pronounced

    the genetic makeup of an individual.

  142. big toe

    the first largest innermost toe
    Usually, only one joint is involved, most commonly the base of a
    big toe.
  143. uric

    in or relating to or obtained from urine
    See phenotype.

    gout click this icon to hear the preceding term pronounced

    a genetically inherited metabolic disorder in which there is an imbalance of
    uric acid in the blood which causes a build up of urates in joint areas.

  144. inheritance

    hereditary succession to a title or an office or property
    The
    inheritance of this syndrome is subject to genome imprinting.
  145. insulate

    surround with material to protect from heat, cold, or noise
    MS occurs as a consequence of one's own immune system attacking the
    insulating sheath that normally protects neurons.
  146. degenerative

    (of illness) marked by gradual deterioration of organs and cells along with loss of function
    Huntington's disease

    a severe genetically inherited fatal
    degenerative nerve disorder.

  147. organism

    a living thing that can act or function independently
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    evolution click this icon to hear the preceding term pronounced

    genetic change in a population of
    organisms that occurs over time.

  148. insulin

    hormone secreted by the isles of Langerhans in the pancreas
    Type 1 diabetes melitis (juvenile onset diabetes) is due to decreased production of
    insulin by the pancreas.
  149. multiple sclerosis

    a chronic progressive nervous disorder involving loss of myelin sheath around certain nerve fibers
    Multiple-allele series only partly follow simple Mendelian genetics.

    multiple sclerosis click this icon to hear the preceding term pronounced (MS)

    a genetically inherited progressive disease of the central nervous system.

  150. Tay

    a branch of the Tai languages
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    Tay-Sachs Disease click this icon to hear the preceding term pronounced

    a genetically inherited condition caused by the inability to produce the enzyme hexosaminidase A. This results in progressively increased fluid pressure on the brain and the subsequent degeneration of the brain and nervous system beginning about 6 months of age and inevitably resulting in death usually by age 2-3.

  151. skeletal

    of or relating to or forming or attached to a skeleton
    MD is characterized by a gradual, irreversible wasting of
    skeletal muscle.
  152. abnormality

    an abnormal physical condition resulting from defective genes or developmental deficiencies
    The next and subsequent generations are referred to as f2, f3, etc.

    fragile-X syndrome click this icon to hear the preceding term pronounced

    a relatively common genetically inherited
    abnormality of the X chromosome which results in mental retardation.

  153. cataract

    disease that involves the clouding of the lens of the eye
    This is the case with hemophilia.

    cataract click this icon to hear the preceding term pronounced

    an impairment of vision caused by the lenses of the eyes becoming cloudy.

  154. subtropical

    of or relating to or characteristic of conditions in the subtropics
    People who spend much of their first 16 years in tropical and
    subtropical regions of the world are much less likely to develop this disease than those who live in far northern and far southern regions of our planet.
  155. Department of Energy

    the federal department responsible for maintaining a national energy policy of the United States; created in 1977
    Department of Energy.
  156. discrete

    constituting a separate entity or part
    In other words, the hereditary material of any organism is made up of
    discrete units (now called genes).

    unstable alleles

    see stuttering alleles.

  157. onset

    the beginning or early stages
    In contrast, an acute disease is one with a rapid
    onset and a short but usually severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-carrying bodies in the nucleus of a cell.

  158. blood sugar

    glucose in the bloodstream
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    diabetes click this icon to hear the preceding term pronounced

    an inherited metabolic disorder in which there are abnormally high
    blood sugar levels.

  159. dysfunction

    any disturbance in the working of an organ or body part
    Most fragile-X males have large testes, big ears, narrow faces, and sensory integration
    dysfunctions that result in learning disabilities.
  160. albino

    a person with white hair, milky skin, and pink eyes
    An individual with these traits is an "
    albino."
  161. pancreas

    a large elongated exocrine gland located behind the stomach
    Type 1 diabetes melitis (juvenile onset diabetes) is due to decreased production of insulin by the
    pancreas.
  162. humans

    all of the living human inhabitants of the earth
    Humans have 46 chromosomes in each somatic cell and 23 in each sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which two different alleles for a trait are expressed unblended in the phenotype of heterozygous individuals.

  163. offspring

    the immediate descendants of a person or organism
    Carriers often do not show any signs of the trait but can pass it on to their
    offspring.
  164. sclerosis

    any pathological hardening or thickening of tissue
    Multiple-allele series only partly follow simple Mendelian genetics.

    multiple
    sclerosis click this icon to hear the preceding term pronounced (MS)

    a genetically inherited progressive disease of the central nervous system.

  165. inflame

    arouse or excite feelings and passions
    Symptoms include painfully
    inflamed joints, especially of the feet and hands, that can become chronic and result in deformity.
  166. twins

    two interwoven crystals that are mirror images on each other
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be explained by simple rules of dominance and recessiveness of genes.

    modifying gene

    a gene that can alter the expression of another gene in the phenotype of an individual.

    monozygotic
    twins click this icon to hear the preceding term pronounced

    identical
    twins.

  167. adulthood

    the period of time in life after physical growth has stopped
    This is ultimately a fatal disease, but with modern medical care, about 2/3 of the people with it survive into early
    adulthood.
  168. irreversible

    incapable of being turned around
    MD is characterized by a gradual,
    irreversible wasting of skeletal muscle.
  169. fertilize

    provide with fertilizers or add nutrients to
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    zygote click this icon to hear the preceding term pronounced

    a "
    fertilized" ovum.

  170. incorrect

    not correct; not in conformity with fact or truth
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    blending theory

    an
    incorrect 19th century theory about the inheritance of characteristics.

  171. pass on

    place into the hands or custody of
    It is a sex-linked trait most often
    passed on to sons by their mothers.
  172. complement

    something added to embellish or make perfect
    Genetics is the branch of science that deals with the inheritance of biological characteristics.

    genome click this icon to hear the preceding term pronounced

    the full genetic
    complement of an individual (or of a species).

  173. compose

    form the substance of
    Proteins are
    composed of different combinations of amino acids assembled in chain-like molecules.
  174. hear

    perceive (sound) via the auditory sense
    albinism click this icon to
    hear the preceding term pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  175. gender

    the biological or cultural traits associated with one sex
    See Human Genome Project.

    genome imprinting click this icon to hear the preceding term pronounced

    an inheritance pattern in which a gene will have a different effect depending on the
    gender of the parent from whom it is inherited.

  176. imbalance

    a lack of stability, evenness, or equilibrium
    See phenotype.

    gout click this icon to hear the preceding term pronounced

    a genetically inherited metabolic disorder in which there is an
    imbalance of uric acid in the blood which causes a build up of urates in joint areas.

  177. parent

    a father or mother
    Cystic fibrosis occurs as a result of inheriting a recessive allele for it from both
    parents.
  178. dominant

    most frequent or common
    Neither allele is
    dominant or recessive, so that both appear in the phenotype or influence it.
  179. nutrient

    any substance that can be metabolized to give energy
    This disease also prevents normal absorption of fats and other
    nutrients from food.
  180. underlie

    be underneath
    Genetic mechanisms are the
    underlying foundation for evolutionary change.
  181. specialize

    become more focused on an area of activity or field of study
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    meiosis click this icon to hear the preceding term pronounced

    cell division in
    specialized tissues of ovaries and testes which results in the production of sperm or ova.

  182. reunite

    connect or come together again
    During fertilization, the full number of chromosomes is restored, and members of gene pairs are
    reunited.

    probability

    the likelihood that a specific event will occur.

  183. get worse

    deteriorate in health
    The most common form, Duchene MD, begins to weaken the legs of boys by age 3 and inevitably
    gets worse with each passing year.
  184. virus

    infectious agent that replicates itself within living hosts
    The gene(s) responsible for MS are incompletely penetrant in that the onset of the disease is apparently triggered by a
    virus and possibly other environmental factors.
  185. first principle

    the elementary stages of any subject (usually plural)
    The genes controlling different traits are inherited independently of one another.

    principle of segregation

    Gregor Mendel's
    first principle of genetic inheritance.

  186. characterize

    be typical of
    MD is
    characterized by a gradual, irreversible wasting of skeletal muscle.
  187. occur

    come to pass
    Cystic fibrosis
    occurs as a result of inheriting a recessive allele for it from both parents.
  188. sex

    one of two categories into which most organisms are divided
    Humans have 46 chromosomes in each somatic cell and 23 in each
    sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which two different alleles for a trait are expressed unblended in the phenotype of heterozygous individuals.

  189. inheriting

    having the legal right to inherit
    Cystic fibrosis occurs as a result of
    inheriting a recessive allele for it from both parents.
  190. immune system

    a system (including the thymus and bone marrow and lymphoid tissues) that protects the body from foreign substances and pathogenic organisms by producing the immune response
    MS occurs as a consequence of one's own
    immune system attacking the insulating sheath that normally protects neurons.
  191. clot

    a lump of material formed from the content of a liquid
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    hemophilia click this icon to hear the preceding term pronounced

    an X-linked genetically inherited recessive disease in which one or more of the normal blood
    clotting factors is not produced.

  192. fertilization

    making productive by adding nutrients
    During
    fertilization, the full number of chromosomes is restored, and members of gene pairs are reunited.

    probability

    the likelihood that a specific event will occur.

  193. twin

    either of two offspring born at the same time from the same pregnancy
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be explained by simple rules of dominance and recessiveness of genes.

    modifying gene

    a gene that can alter the expression of another gene in the phenotype of an individual.

    monozygotic
    twins click this icon to hear the preceding term pronounced

    identical
    twins.

  194. mutation

    a change or alteration in form or qualities
    There is no cure for this disorder, and it usually results in death before the age of 30.

    mutation click this icon to hear the preceding term pronounced

    an alteration of genetic material such that a new variation is produced.

  195. gangrene

    the localized death of living cells
    In advanced stages, this often results in blindness from cataracts, nerve damage,
    gangrene in the feet and legs leading to amputation, heart disease, and kidney failure.
  196. dominance

    the power or right to give orders or make decisions
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be explained by simple rules of
    dominance and recessiveness of genes.

    modifying gene

    a gene that can alter the expression of another gene in the phenotype of an individual.

    monozygotic twins click this icon to hear the preceding term pronounced

    identical twins.

  197. makeup

    the way in which someone or something is composed
    Genome imprinting is also known as genetic imprinting.

    genotype click this icon to hear the preceding term pronounced

    the genetic
    makeup of an individual.

  198. daunt

    cause to lose courage
    This decoding of the human proteome will be an even more
    daunting task than the original Human Genome Project.
  199. disease

    an impairment of health
    They may be inherited or caused by diabetes and environmental factors.

    photo of a normal eye and another with a cataract

    chronic
    disease

    an illness that lasts for a long period of time or indefinitely.

  200. distort

    twist and press out of shape
    See sex-controlled gene.

    sickle-cell trait

    a genetically inherited recessive condition in which red blood cells are
    distorted resulting in severe anemia and related symptoms that are often fatal in childhood.

  201. Mendel

    Augustinian monk and botanist whose experiments in breeding garden peas led to his eventual recognition as founder of the science of genetics (1822-1884)
    Through his plant cross-breeding experiments, Gregor
    Mendel proved that this was wrong

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    carrier

    an individual who is heterozygous for a trait that only shows up in the phenotype of those who are homozygous recessive.

  202. blend

    mix together different elements
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    blending theory

    an incorrect 19th century theory about the inheritance of characteristics.

  203. breeding

    the activity of conceiving and bearing offspring
    Through his plant cross-
    breeding experiments, Gregor Mendel proved that this was wrong

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    carrier

    an individual who is heterozygous for a trait that only shows up in the phenotype of those who are homozygous recessive.

  204. frequency

    the number of occurrences within a given time period
    The loss or addition of individuals can easily change the gene pool
    frequencies of both the recipient and donor populations--that is, they can evolve.

    gene pool

    all of the genes in all of the individuals in a breeding population.

  205. numbness

    partial or total lack of sensation in a part of the body
    Symptoms range from
    numbness and tingling to paralysis.
  206. ovary

    (vertebrates) one of usually two organs that produce ova and secrete estrogen and progesterone
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    meiosis click this icon to hear the preceding term pronounced

    cell division in specialized tissues of
    ovaries and testes which results in the production of sperm or ova.

  207. multinational

    involving or operating in several nations or nationalities
    Human Genome Project

    a
    multinational research effort designed to identify and map the location of all human genes.

  208. disorder

    a condition in which things are not in their expected places
    Children with Angleman syndrome typically also have small heads, experience seizures, have pronounced speech impairment, are hyperactive, and have balance
    disorders.
  209. refer

    make a remark that calls attention to
    The term is also frequently used to
    refer to the appearance of a new species.
  210. be due

    be the result of
    Type 1 diabetes melitis (juvenile onset diabetes)
    is due to decreased production of insulin by the pancreas.
  211. acid

    a sour water-soluble compound with a pH of less than 7
    However, because they are different, their action may result in different expressions of that trait.

    amino
    acids click this icon to hear the preceding term pronounced

    small molecules that are the components of proteins.

  212. multiple

    having or involving more than one part or entity
    The HLA system has the most genes of any other known human
    multiple-allele series.
  213. transference

    the act of moving something from one form to another
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    gene flow

    the
    transference of genes from one population to another, usually as a result of migration.

  214. Charles Darwin

    English natural scientist who formulated a theory of evolution by natural selection (1809-1882)
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    pangenesis click this icon to hear the preceding term pronounced

    Charles Darwin's incorrect theory about the inheritance of traits.

  215. unstable

    subject to change; variable
    Stuttering alleles are also known as
    unstable alleles.
  216. breed

    cause to procreate (animals)
    Through his plant cross-
    breeding experiments, Gregor Mendel proved that this was wrong

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    carrier

    an individual who is heterozygous for a trait that only shows up in the phenotype of those who are homozygous recessive.

  217. amputation

    a surgical removal of all or part of a limb
    In advanced stages, this often results in blindness from cataracts, nerve damage, gangrene in the feet and legs leading to
    amputation, heart disease, and kidney failure.
  218. result

    something that follows as a consequence
    However, because they are different, their action may
    result in different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that are the components of proteins.

  219. migrate

    move from one country or region to another and settle there
    These modified particles were thought to
    migrate via blood to the reproductive cells and subsequently could be inherited by the next generation.
  220. progressively

    advancing in amount or intensity
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    Tay-Sachs Disease click this icon to hear the preceding term pronounced

    a genetically inherited condition caused by the inability to produce the enzyme hexosaminidase A. This results in
    progressively increased fluid pressure on the brain and the subsequent degeneration of the brain and nervous system beginning about 6 months of age and inevitably resulting in death usually by age 2-3.

  221. sensory

    relating to or concerned in sensation
    Most fragile-X males have large testes, big ears, narrow faces, and
    sensory integration dysfunctions that result in learning disabilities.
  222. bleed

    lose blood from one's body
    This results in prolonged
    bleeding from even minor cuts and injuries.
  223. daunting

    discouraging through fear
    This decoding of the human proteome will be an even more
    daunting task than the original Human Genome Project.
  224. cognitive

    relating to or involving the mental process of knowing
    There is a loss of motor and
    cognitive functions.
  225. abnormally

    in an abnormal manner
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    diabetes click this icon to hear the preceding term pronounced

    an inherited metabolic disorder in which there are
    abnormally high blood sugar levels.

  226. component

    one of the individual parts making up a larger entity
    However, because they are different, their action may result in different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that are the
    components of proteins.

  227. show up

    appear or become visible; make a showing
    Since the gene for albinism is recessive, it only
    shows up in the phenotype of homozygous recessive people.
  228. individual

    being or characteristic of a single thing or person
    An
    individual with these traits is an "albino."
  229. Lamarck

    French naturalist who proposed that evolution resulted from the inheritance of acquired characteristics (1744-1829)
    This was a variation of
    Lamarck's incorrect idea of the "inheritance of acquired characteristics."

    phenotype click this icon to hear the preceding term pronounced

    the observable or detectable characteristics of an individual organism--the detectable expression of a genotype.

    pleiotropy click this icon to hear the preceding term pronounced

    the situation in which a single gene is responsible for a variety of traits.

  230. nervous system

    the sensory and control apparatus consisting of a network of nerve cells
    Multiple-allele series only partly follow simple Mendelian genetics.

    multiple sclerosis click this icon to hear the preceding term pronounced (MS)

    a genetically inherited progressive disease of the central
    nervous system.

  231. gout

    a painful inflammation of the big toe and foot caused by defects in uric acid metabolism resulting in deposits of the acid and its salts in the blood and joints
    See phenotype.

    gout click this icon to hear the preceding term pronounced

    a genetically inherited metabolic disorder in which there is an imbalance of uric acid in the blood which causes a build up of urates in joint areas.

  232. environmental

    of or relating to the external conditions or surroundings
    They may be inherited or caused by diabetes and
    environmental factors.

    photo of a normal eye and another with a cataract

    chronic disease

    an illness that lasts for a long period of time or indefinitely.

  233. segment

    one of several parts that fit with others to make a whole
    Segments of DNA in chromosomes correspond to specific genes.
  234. chronic

    long-lasting or characterized by long suffering
    They may be inherited or caused by diabetes and environmental factors.

    photo of a normal eye and another with a cataract


    chronic disease

    an illness that lasts for a long period of time or indefinitely.

  235. top

    the upper part of anything
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    - B -

    blending theory

    an incorrect 19th century theory about the inheritance of characteristics.

  236. approximately

    imprecise but fairly close to correct
    Approximately 1 in 700 females are carriers of the gene for this trait.
  237. hybrid

    a composite of mixed origin
    This disease is also called Huntington's chorea click this icon to hear the preceding term pronounced.

    hybrids click this icon to hear the preceding term pronounced

    offspring that are the result of mating between two genetically different kinds of parents--the opposite of purebred.

  238. intermediate

    lying between two extremes in time, space, or state
    The triggering of genetically inherited diabetes by obesity and possibly severe emotional stress is an example.

    intermediate expression

    the situation in which a heterozygous genotype results in a phenotype that is
    intermediate between those resulting from the homozygous genotypes.

  239. muscle

    animal tissue consisting predominantly of contractile cells
    There is a progressive loss of
    muscle control that inevitably leads to paralysis and death.
  240. linked

    connected, as railway cars or trailer trucks
    Since it is an X-
    linked trait, males more often have it expressed in their phenotypes.
  241. paralysis

    loss of the ability to move a body part
    There is a progressive loss of muscle control that inevitably leads to
    paralysis and death.
  242. medical care

    professional treatment for illness or injury
    This is ultimately a fatal disease, but with modern
    medical care, about 2/3 of the people with it survive into early adulthood.
  243. reproduce

    make a copy or equivalent of
    They
    reproduce by mitosis.
  244. generation

    group of genetically related organisms in a line of descent
    It proposed that inherited traits blend from
    generation to
    generation.
  245. modify

    cause to change; make different
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be explained by simple rules of dominance and recessiveness of genes.

    modifying gene

    a gene that can alter the expression of another gene in the phenotype of an individual.

    monozygotic twins click this icon to hear the preceding term pronounced

    identical twins.

  246. paired

    used of gloves, socks, etc.
    HLA stands for "human leukocyte antigen" click this icon to hear the preceding term pronounced.

    homeotic gene click this icon to hear the preceding term pronounced

    see regulator gene.

    homologous chromosomes click this icon to hear the preceding term pronounced

    chromosomes that are
    paired during the production of of sex cells in meiosis.

  247. responsible for

    being the agent or cause
    Genes are
    responsible for the hereditary traits in plants and animals.

    genetic drift

    evolution, or change in gene pool frequencies, resulting from random chance.

  248. correlation

    a reciprocal connection between two or more things
    There is a
    correlation between the amount of sunlight that children are exposed to and the likelihood that they will develop MS later in life.
  249. Twins

    the third sign of the zodiac
    Twins that come from the same zygote are essentially the same genetically.
  250. likelihood

    the probability of a specified outcome
    There is a correlation between the amount of sunlight that children are exposed to and the
    likelihood that they will develop MS later in life.
  251. factor

    anything that contributes causally to a result
    They may be inherited or caused by diabetes and environmental
    factors.

    photo of a normal eye and another with a cataract

    chronic disease

    an illness that lasts for a long period of time or indefinitely.

  252. baritone

    the second lowest adult male singing voice
    The mid-range
    baritone male voice is an example.
  253. degeneration

    the process of declining from a higher to a lower level
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    - T -

    Tay-Sachs Disease click this icon to hear the preceding term pronounced

    a genetically inherited condition caused by the inability to produce the enzyme hexosaminidase A. This results in progressively increased fluid pressure on the brain and the subsequent
    degeneration of the brain and nervous system beginning about 6 months of age and inevitably resulting in death usually by age 2-3.

  254. strictly speaking

    in actual fact
    Since viruses cannot reproduce without a host cell, they are not
    strictly speaking living organisms.
  255. hormone

    the secretion of an endocrine gland transmitted by the blood
    Proteins may be enzymes,
    hormones, antibodies, structural components, or gas-transporting molecules.

    proteome click this icon to hear the preceding term pronounced

    the full complement of proteins produced by an individual (or a species).

  256. carrier

    a person or firm transporting people or goods or messages
    Through his plant cross-breeding experiments, Gregor Mendel proved that this was wrong

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    - C -

    carrier

    an individual who is heterozygous for a trait that only shows up in the phenotype of those who are homozygous recessive.

  257. pair

    a set of two similar things considered as a unit
    HLA stands for "human leukocyte antigen" click this icon to hear the preceding term pronounced.

    homeotic gene click this icon to hear the preceding term pronounced

    see regulator gene.

    homologous chromosomes click this icon to hear the preceding term pronounced

    chromosomes that are
    paired during the production of of sex cells in meiosis.

  258. interaction

    mutual or reciprocal dealings or influence
    Simple Mendelian rules of dominance do not apply to the complex
    interaction of these genes.
  259. initiate

    set in motion, start an event or prepare the way for
    Recessive alleles are expressed in the phenotype when the genotype is homozygous recessive (aa).

    regulator gene

    a gene that can
    initiate or block the functions of other genes.

  260. male

    being the sex that performs the fertilizing function
    Since it is an X-linked trait,
    males more often have it expressed in their phenotypes.
  261. particle

    (nontechnical usage) a tiny piece of anything
    He proposed that hereditary
    particles in the body are affected by the things an individual does during his or her lifetime.
  262. random

    lacking any definite plan or order or purpose
    Genes are responsible for the hereditary traits in plants and animals.

    genetic drift

    evolution, or change in gene pool frequencies, resulting from
    random chance.

  263. phosphate

    a salt of phosphoric acid
    DNA is composed of sugars,
    phosphates and bases arranged in a double helix shaped molecular structure.
  264. unit

    a single undivided whole
    More precisely, it is the collective genotype of a population.

    genes click this icon to hear the preceding term pronounced

    units of inheritance usually occurring at specific locations, or loci, on a chromosome.

  265. inflamed

    resulting from inflammation; hot and swollen and reddened
    Symptoms include painfully
    inflamed joints, especially of the feet and hands, that can become chronic and result in deformity.
  266. involve

    contain as a part
    Usually, only one joint is
    involved, most commonly the base of a big toe.
  267. parasite

    an animal or plant that lives in or on a host
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    - V -

    virus click this icon to hear the preceding term pronounced

    a category of extremely small microscopic
    parasites of plants, animals, and bacteria.

  268. specify

    be particular about
    Physically, a gene is a sequence of DNA bases that
    specify the order of amino acids in an entire protein or, in some cases, a portion of a protein.
  269. afflict

    cause physical pain or suffering in
    Hemophilia most often
    afflicts males.

    heterozygous click this icon to hear the preceding term pronounced

    a genotype consisting of two different alleles of a gene for a particular trait (Aa).

  270. counselor

    someone who gives advice about problems
    Punnett squares are commonly used by genetics
    counselors to predict the odds of a couple passing on particular inherited traits.

    illustration of how to set up a Punnett square

    purebred click this icon to hear the preceding term pronounced

    offspring that are the result of mating between genetically similar kinds of parents--the opposite of hybrid.

  271. evolve

    undergo development
    The loss or addition of individuals can easily change the gene pool frequencies of both the recipient and donor populations--that is, they can
    evolve.

    gene pool

    all of the genes in all of the individuals in a breeding population.

  272. synthesis

    the combination of ideas into a complex whole
    DNA click this icon to hear the preceding term pronounced (deoxyribonucleic acid click this icon to hear the preceding term pronounced)

    a large organic molecule that stores the genetic code for the
    synthesis of proteins.

  273. transplant

    transfer from one place or period to another
    HLA system click this icon to hear the preceding term pronounced

    the body's genetically inherited system for recognizing and rejecting foreign tissues, such as
    transplanted organs.

  274. deviation

    a variation from the standard or norm
    In large populations, random
    deviations in allele frequencies in one direction are more likely to be cancelled out by random changes in the opposite direction.

    genetics click this icon to hear the preceding term pronounced

    the study of gene structure and action and the patterns of inheritance of traits from parent to offspring.

  275. evolutionary

    relating to the development of a species
    Genetic mechanisms are the underlying foundation for
    evolutionary change.
  276. reproductive

    producing new life or offspring
    These modified particles were thought to migrate via blood to the
    reproductive cells and subsequently could be inherited by the next generation.
  277. hereditary

    occurring among people descended from a common ancestor
    Genes are responsible for the
    hereditary traits in plants and animals.

    genetic drift

    evolution, or change in gene pool frequencies, resulting from random chance.

  278. usually

    under normal conditions
    In contrast, an acute disease is one with a rapid onset and a short but
    usually severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-carrying bodies in the nucleus of a cell.

  279. segregation

    the act of keeping apart
    The genes controlling different traits are inherited independently of one another.

    principle of
    segregation

    Gregor Mendel's first principle of genetic inheritance.

  280. function

    what something is used for
    There is a loss of motor and cognitive
    functions.
  281. tingling

    a somatic sensation as from many tiny prickles
    Symptoms range from numbness and
    tingling to paralysis.
  282. progressive

    favoring or promoting modern or innovative ideas
    There is a
    progressive loss of muscle control that inevitably leads to paralysis and death.
  283. molecular

    relating to the simplest units of an element or compound
    DNA is composed of sugars, phosphates and bases arranged in a double helix shaped
    molecular structure.
  284. independently

    on your own; without outside help
    It states that different pairs of genes are passed to offspring
    independently so that new combinations of genes, present in neither parent, are possible.
  285. disability

    when one cannot perform due to physical or mental unfitness
    Most fragile-X males have large testes, big ears, narrow faces, and sensory integration dysfunctions that result in learning
    disabilities.
  286. link

    connect, fasten, or put together two or more pieces
    Since it is an X-
    linked trait, males more often have it expressed in their phenotypes.
  287. fragile

    easily broken or damaged or destroyed
    The next and subsequent generations are referred to as f2, f3, etc.

    fragile-X syndrome click this icon to hear the preceding term pronounced

    a relatively common genetically inherited abnormality of the X chromosome which results in mental retardation.

  288. recur

    happen or occur again
    See Human Genome Project.

    psoriasis click this icon to hear the preceding term pronounced

    an inherited disease characterized by
    recurring thick, reddish patches of inflamed skin.

  289. fraternal

    like or characteristic of or befitting a brother
    Fraternal twins may look similar but are not genetically identical.

    multiple-allele series click this icon to hear the preceding term pronounced

    a situation in which a gene has more than two alleles.

  290. microscopic

    so small as to be invisible without a magnifying device
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    - V -

    virus click this icon to hear the preceding term pronounced

    a category of extremely small
    microscopic parasites of plants, animals, and bacteria.

  291. inevitably

    in such a manner as could not be otherwise
    There is a progressive loss of muscle control that
    inevitably leads to paralysis and death.
  292. period of time

    an amount of time
    They may be inherited or caused by diabetes and environmental factors.

    photo of a normal eye and another with a cataract

    chronic disease

    an illness that lasts for a long
    period of time or indefinitely.

  293. observable

    capable of being seen or noticed
    This was a variation of Lamarck's incorrect idea of the "inheritance of acquired characteristics."

    phenotype click this icon to hear the preceding term pronounced

    the
    observable or detectable characteristics of an individual organism--the detectable expression of a genotype.

    pleiotropy click this icon to hear the preceding term pronounced

    the situation in which a single gene is responsible for a variety of traits.

  294. living thing

    a living (or once living) entity
    There are 20 different kinds of amino acids in
    living things.
  295. express

    communicate beliefs or opinions
    Humans have 46 chromosomes in each somatic cell and 23 in each sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which two different alleles for a trait are
    expressed unblended in the phenotype of heterozygous individuals.

  296. cancelled

    no longer planned or scheduled
    In large populations, random deviations in allele frequencies in one direction are more likely to be
    cancelled out by random changes in the opposite direction.

    genetics click this icon to hear the preceding term pronounced

    the study of gene structure and action and the patterns of inheritance of traits from parent to offspring.

  297. trigger

    lever that activates the firing mechanism of a gun
    The
    triggering of genetically inherited diabetes by obesity and possibly severe emotional stress is an example.

    intermediate expression

    the situation in which a heterozygous genotype results in a phenotype that is intermediate between those resulting from the homozygous genotypes.

  298. identical

    being the exact same one
    Homozygous also refers to a genotype consisting of two
    identical alleles of a gene for a particular trait.
  299. deformity

    an affliction in which some part of the body is misshapen
    Symptoms include painfully inflamed joints, especially of the feet and hands, that can become chronic and result in
    deformity.
  300. coating

    a thin layer covering something
    Viruses are not cells but rather RNA or DNA molecules surrounded by a protein
    coating.
  301. responsible

    worthy of or requiring trust; held accountable
    Genes are
    responsible for the hereditary traits in plants and animals.

    genetic drift

    evolution, or change in gene pool frequencies, resulting from random chance.

  302. obesity

    the condition of being excessively overweight
    The triggering of genetically inherited diabetes by
    obesity and possibly severe emotional stress is an example.

    intermediate expression

    the situation in which a heterozygous genotype results in a phenotype that is intermediate between those resulting from the homozygous genotypes.

  303. assortment

    the act of distributing things into classes of the same type
    Many polygenic traits are also influenced by environmental factors.

    principle of independent
    assortment

    Gregor Mendel's second principle of genetic inheritance.

  304. specific

    stated explicitly or in detail
    Angelman syndrome click this icon to hear the preceding term pronounced

    a rare genetically inherited form of mental retardation due to the deletion or inactivation of
    specific genes on chromosome 15.

  305. funded

    furnished with funds
    Research to decode the human genome began in earnest in 1986,
    funded by the U.S.
  306. in other words

    otherwise stated
    In other words, the distribution of one pair of alleles does not influence the distribution of another pair.
  307. collective

    done by or characteristic of individuals acting together
    More precisely, it is the
    collective genotype of a population.

    genes click this icon to hear the preceding term pronounced

    units of inheritance usually occurring at specific locations, or loci, on a chromosome.

  308. characteristic

    typical or distinctive
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    - B -

    blending theory

    an incorrect 19th century theory about the inheritance of
    characteristics.

  309. expressed

    communicated in words
    Humans have 46 chromosomes in each somatic cell and 23 in each sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which two different alleles for a trait are
    expressed unblended in the phenotype of heterozygous individuals.

  310. tissue

    part of an organism consisting of an aggregate of cells
    HLA system click this icon to hear the preceding term pronounced

    the body's genetically inherited system for recognizing and rejecting foreign
    tissues, such as transplanted organs.

  311. location

    the act of putting something in a certain place
    More precisely, it is the collective genotype of a population.

    genes click this icon to hear the preceding term pronounced

    units of inheritance usually occurring at specific
    locations, or loci, on a chromosome.

  312. probability

    a measure of how likely it is that some event will occur
    During fertilization, the full number of chromosomes is restored, and members of gene pairs are reunited.

    probability

    the likelihood that a specific event will occur.

  313. human

    a person; a hominid with a large brain and articulate speech
    Humans have 46 chromosomes in each somatic cell and 23 in each sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which two different alleles for a trait are expressed unblended in the phenotype of heterozygous individuals.

  314. controlled

    restrained or managed or kept within certain bounds
    Gout is a sex-
    controlled trait, usually being more severe in men.
  315. heart disease

    a disease of the heart
    In advanced stages, this often results in blindness from cataracts, nerve damage, gangrene in the feet and legs leading to amputation,
    heart disease, and kidney failure.
  316. mechanism

    device consisting of a piece of machinery
    Genetic
    mechanisms are the underlying foundation for evolutionary change.
  317. severe

    unsparing and uncompromising in discipline or judgment
    In contrast, an acute disease is one with a rapid onset and a short but usually
    severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-carrying bodies in the nucleus of a cell.

  318. muscular

    having a robust body-build
    It is believed that the lack of abundant sun exposure early in life is somehow responsible for the later onset of MS.

    muscular dystrophy click this icon to hear the preceding term pronounced (MD)

    any of a group of inherited progressive muscle disorders caused by a defect in one or more genes that control muscle function.

  319. donor

    a person who makes a gift of money, property, etc.
    The loss or addition of individuals can easily change the gene pool frequencies of both the recipient and
    donor populations--that is, they can evolve.

    gene pool

    all of the genes in all of the individuals in a breeding population.

  320. middle age

    the time of life between youth and old age
    The symptoms usually do not appear until early
    middle age.
  321. blending

    the act of blending components together thoroughly
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    - B -

    blending theory

    an incorrect 19th century theory about the inheritance of characteristics.

  322. recurring

    coming back
    See Human Genome Project.

    psoriasis click this icon to hear the preceding term pronounced

    an inherited disease characterized by
    recurring thick, reddish patches of inflamed skin.

  323. sheath

    a protective covering, as for a knife or sword
    MS occurs as a consequence of one's own immune system attacking the insulating
    sheath that normally protects neurons.
  324. immune

    of the condition in which an organism can resist disease
    MS occurs as a consequence of one's own
    immune system attacking the insulating sheath that normally protects neurons.
  325. only if

    never except when
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    - I -

    incomplete penetrance

    the situation in which an allele is expressed
    only if certain factors are present in the environment.

  326. kidney

    either of two bean-shaped excretory organs that filter wastes (especially urea) from the blood and excrete them and water in urine
    In advanced stages, this often results in blindness from cataracts, nerve damage, gangrene in the feet and legs leading to amputation, heart disease, and
    kidney failure.
  327. filial

    designating the generation following the parental generation
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    - F -

    f1 generation click this icon to hear the preceding term pronounced

    the first offspring (or
    filial) generation.

  328. decreased

    made less in size or amount or degree
    Type 1 diabetes melitis (juvenile onset diabetes) is due to
    decreased production of insulin by the pancreas.
  329. joint

    junction by which parts or objects are linked together
    See phenotype.

    gout click this icon to hear the preceding term pronounced

    a genetically inherited metabolic disorder in which there is an imbalance of uric acid in the blood which causes a build up of urates in
    joint areas.

  330. identify

    recognize as being
    Human Genome Project

    a multinational research effort designed to
    identify and map the location of all human genes.

  331. produce

    bring forth or yield
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    - H -

    hemophilia click this icon to hear the preceding term pronounced

    an X-linked genetically inherited recessive disease in which one or more of the normal blood clotting factors is not
    produced.

  332. base

    lowest support of a structure
    DNA is composed of sugars, phosphates and
    bases arranged in a double helix shaped molecular structure.
  333. specialized

    developed or designed for a particular activity or function
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    - J -

    Back to Top

    - K -

    Back to Top

    - L -

    Back to Top

    - M -

    meiosis click this icon to hear the preceding term pronounced

    cell division in
    specialized tissues of ovaries and testes which results in the production of sperm or ova.

  334. evolution

    sequence of events involved in the development of a species
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    - E -

    evolution click this icon to hear the preceding term pronounced

    genetic change in a population of organisms that occurs over time.

  335. variation

    the process of being or becoming different
    There is no cure for this disorder, and it usually results in death before the age of 30.

    mutation click this icon to hear the preceding term pronounced

    an alteration of genetic material such that a new
    variation is produced.

  336. integration

    the act of combining into a whole
    Most fragile-X males have large testes, big ears, narrow faces, and sensory
    integration dysfunctions that result in learning disabilities.
  337. fluid

    continuous amorphous matter that tends to flow
    Usually, the term is used in reference to the crossing of two pure breeding (homozygous) plants.

    cystic fibrosis click this icon to hear the preceding term pronounced

    a genetically inherited disease in children that results in chronic
    fluid development in the lungs, making breathing difficult.

  338. primarily

    for the most part
    Amino acids are
    primarily composed of carbon, oxygen, hydrogen, and nitrogen.
  339. pattern

    a perceptual structure
    In large populations, random deviations in allele frequencies in one direction are more likely to be cancelled out by random changes in the opposite direction.

    genetics click this icon to hear the preceding term pronounced

    the study of gene structure and action and the
    patterns of inheritance of traits from parent to offspring.

  340. plant

    a living organism without the power to move
    Through his
    plant cross-breeding experiments, Gregor Mendel proved that this was wrong

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    - C -

    carrier

    an individual who is heterozygous for a trait that only shows up in the phenotype of those who are homozygous recessive.

  341. prolong

    lengthen in time; cause to be or last longer
    This results in
    prolonged bleeding from even minor cuts and injuries.
  342. structural

    relating to the composition of something
    Proteins may be enzymes, hormones, antibodies,
    structural components, or gas-transporting molecules.

    proteome click this icon to hear the preceding term pronounced

    the full complement of proteins produced by an individual (or a species).

  343. composed

    serenely self-possessed and free from agitation
    Proteins are
    composed of different combinations of amino acids assembled in chain-like molecules.
  344. cancel

    declare null and void
    In large populations, random deviations in allele frequencies in one direction are more likely to be
    cancelled out by random changes in the opposite direction.

    genetics click this icon to hear the preceding term pronounced

    the study of gene structure and action and the patterns of inheritance of traits from parent to offspring.

  345. seizure

    the taking possession of something by legal process
    Children with Angleman syndrome typically also have small heads, experience
    seizures, have pronounced speech impairment, are hyperactive, and have balance disorders.
  346. consist

    have its essential character
    Hemophilia most often afflicts males.

    heterozygous click this icon to hear the preceding term pronounced

    a genotype
    consisting of two different alleles of a gene for a particular trait (Aa).

  347. nucleus

    a part of the cell responsible for growth and reproduction
    In contrast, an acute disease is one with a rapid onset and a short but usually severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-carrying bodies in the
    nucleus of a cell.

  348. bleeding

    the flow of blood from a ruptured blood vessel
    This results in prolonged
    bleeding from even minor cuts and injuries.
  349. pool

    a small body of standing water (rainwater) or other liquid
    The loss or addition of individuals can easily change the gene
    pool frequencies of both the recipient and donor populations--that is, they can evolve.

    gene
    pool

    all of the genes in all of the individuals in a breeding population.

  350. masked

    having markings suggestive of a mask
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    - Q -

    Back to Top

    - R -

    recessive allele click this icon to hear the preceding term pronounced

    an allele that is
    masked in the phenotype by the presence of a dominant allele.

  351. nitrogen

    a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues
    Amino acids are primarily composed of carbon, oxygen, hydrogen, and
    nitrogen.
  352. timing

    the regulation of occurrence, pace, or coordination to achieve a desired effect (as in music, theater, athletics, mechanics)
    Regulator genes control the
    timing of production of a variety of chemicals in humans and other organisms.
  353. reddish

    of a color at the end of the color spectrum
    See Human Genome Project.

    psoriasis click this icon to hear the preceding term pronounced

    an inherited disease characterized by recurring thick,
    reddish patches of inflamed skin.

  354. occurrence

    an instance of something happening
    Probability is usually expressed as the ratio of the number of actual
    occurrences to the number of possible
    occurrences.

    proteins click this icon to hear the preceding term pronounced

    any of a large number of complex organic molecules that are composed of one or more chains of amino acids.

  355. develop

    progress or evolve through a process of natural growth
    There is a correlation between the amount of sunlight that children are exposed to and the likelihood that they will
    develop MS later in life.
  356. absorption

    a process in which one substance permeates another
    This disease also prevents normal
    absorption of fats and other nutrients from food.
  357. build up

    enlarge, develop, or increase by degrees or in stages
    See phenotype.

    gout click this icon to hear the preceding term pronounced

    a genetically inherited metabolic disorder in which there is an imbalance of uric acid in the blood which causes a
    build up of urates in joint areas.

  358. lung

    either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood
    Usually, the term is used in reference to the crossing of two pure breeding (homozygous) plants.

    cystic fibrosis click this icon to hear the preceding term pronounced

    a genetically inherited disease in children that results in chronic fluid development in the
    lungs, making breathing difficult.

  359. organic

    having properties characteristic of living beings
    DNA click this icon to hear the preceding term pronounced (deoxyribonucleic acid click this icon to hear the preceding term pronounced)

    a large
    organic molecule that stores the genetic code for the synthesis of proteins.

  360. population

    the people who inhabit a territory or state
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    - E -

    evolution click this icon to hear the preceding term pronounced

    genetic change in a
    population of organisms that occurs over time.

  361. drift

    be in motion due to some air or water current
    Genes are responsible for the hereditary traits in plants and animals.

    genetic
    drift

    evolution, or change in gene pool frequencies, resulting from random chance.

  362. juvenile

    of or relating to children or young people
    Type 1 diabetes melitis (
    juvenile onset diabetes) is due to decreased production of insulin by the pancreas.
  363. biological

    pertaining to life and living things
    Genetics is the branch of science that deals with the inheritance of
    biological characteristics.

    genome click this icon to hear the preceding term pronounced

    the full genetic complement of an individual (or of a species).

  364. mask

    a covering to disguise or conceal the face
    The gene or genes for diabetes are incompletely penetrant.

    dominant allele

    an allele that
    masks the presence of a recessive allele in the phenotype.

  365. weaken

    lessen the strength of
    The most common form, Duchene MD, begins to
    weaken the legs of boys by age 3 and inevitably gets worse with each passing year.
  366. combination

    the act of bringing things together to form a new whole
    Proteins are composed of different
    combinations of amino acids assembled in chain-like molecules.
  367. plural

    grammatical number category referring to two or more items
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    - N -

    Back to Top

    - O -

    ovum click this icon to hear the preceding term pronounced (
    plural ova click this icon to hear the preceding term pronounced)

    a female sex cell or gamete.

  368. control

    power to direct or determine
    Gout is a sex-
    controlled trait, usually being more severe in men.
  369. bacteria

    single-celled organisms that can cause disease
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    - V -

    virus click this icon to hear the preceding term pronounced

    a category of extremely small microscopic parasites of plants, animals, and
    bacteria.

  370. timely

    done or happening at the appropriate moment
    Shortly after conception, regulator genes work as master switches orchestrating the
    timely development of our body parts.
  371. deficiency

    lack of an adequate quantity or number
    albinism click this icon to hear the preceding term pronounced

    the genetically inherited condition in which there is a marked
    deficiency of pigmentation in skin, hair, and eyes.

  372. descendant

    a person considered as coming from some ancestor or race
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    - U -

    unit inheritance

    Gregor Mendel's idea that the characteristics of parents are passed on to
    descendants unchanged as units.

  373. project

    a planned undertaking
    See Human Genome
    Project.

    genome imprinting click this icon to hear the preceding term pronounced

    an inheritance pattern in which a gene will have a different effect depending on the gender of the parent from whom it is inherited.

  374. mate

    a person's partner in marriage
    Such traits are said to be codominant.

    cross-pollination

    the
    mating of two genetically different plants of the same species.

  375. depending on

    determined by conditions or circumstances that follow
    See Human Genome Project.

    genome imprinting click this icon to hear the preceding term pronounced

    an inheritance pattern in which a gene will have a different effect
    depending on the gender of the parent from whom it is inherited.

  376. decrease

    a change downward
    Type 1 diabetes melitis (juvenile onset diabetes) is due to
    decreased production of insulin by the pancreas.
  377. type

    a subdivision of a particular kind of thing
    Type AB blood is an example.
  378. predict

    tell in advance
    Punnett squares are commonly used by genetics counselors to
    predict the odds of a couple passing on particular inherited traits.

    illustration of how to set up a Punnett square

    purebred click this icon to hear the preceding term pronounced

    offspring that are the result of mating between genetically similar kinds of parents--the opposite of hybrid.

  379. production

    the act or process of making something
    Type 1 diabetes melitis (juvenile onset diabetes) is due to decreased
    production of insulin by the pancreas.
  380. example

    an item of information that is typical of a class or group
    Type AB blood is an
    example.
  381. indefinitely

    to an unknown extent
    They may be inherited or caused by diabetes and environmental factors.

    photo of a normal eye and another with a cataract

    chronic disease

    an illness that lasts for a long period of time or
    indefinitely.

  382. Jew

    member of a community whose traditional religion is Judaism
    It has been most common among the descendents of Eastern European
    Jews (Ashkenazi
    Jews).

    true breeding

    see purebred.

  383. 1000

    the cardinal number that is the product of 10 and 100
    It is likely to occur 1 in
    1000 births.
  384. variety

    a category of things distinguished by a common quality
    This is a pleiotropic trait.

    alleles click this icon to hear the preceding term pronounced

    alternate forms or
    varieties of a gene.

  385. nerve

    a bundle of fibers running to organs and tissues of the body
    In advanced stages, this often results in blindness from cataracts,
    nerve damage, gangrene in the feet and legs leading to amputation, heart disease, and kidney failure.
  386. hydrogen

    a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe
    Amino acids are primarily composed of carbon, oxygen,
    hydrogen, and nitrogen.
  387. blindness

    the state of being blind or lacking sight
    In advanced stages, this often results in
    blindness from cataracts, nerve damage, gangrene in the feet and legs leading to amputation, heart disease, and kidney failure.
  388. transmission

    communication by means of sent signals
    See sex cell.

    sperm click this icon to hear the preceding term pronounced

    a male sex cell or gamete.

    stuttering alleles

    defective alleles that have segments which are doubled in their
    transmission from generation to generation.

  389. contain

    hold or have within
    Meiosis involves two divisions and results in four daughter cells, each
    containing only half the original number of chromosomes--23 in the case of humans.
  390. incomplete

    not total or final
    Back to Top

    - I -

    incomplete penetrance

    the situation in which an allele is expressed only if certain factors are present in the environment.

  391. correspond

    take the place of or be parallel or equivalent to
    Segments of DNA in chromosomes
    correspond to specific genes.
  392. normal

    being approximately average or within certain limits
    They may be inherited or caused by diabetes and environmental factors.

    photo of a
    normal eye and another with a cataract

    chronic disease

    an illness that lasts for a long period of time or indefinitely.

  393. alternate

    go back and forth
    This is a pleiotropic trait.

    alleles click this icon to hear the preceding term pronounced

    alternate forms or varieties of a gene.

  394. cloudy

    full of or covered with clouds
    This is the case with hemophilia.

    cataract click this icon to hear the preceding term pronounced

    an impairment of vision caused by the lenses of the eyes becoming
    cloudy.

  395. defective

    having a flaw
    See sex cell.

    sperm click this icon to hear the preceding term pronounced

    a male sex cell or gamete.

    stuttering alleles

    defective alleles that have segments which are doubled in their transmission from generation to generation.

  396. unchanged

    not made or become different
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    - U -

    unit inheritance

    Gregor Mendel's idea that the characteristics of parents are passed on to descendants
    unchanged as units.

  397. distorted

    so badly formed or out of shape as to be ugly
    See sex-controlled gene.

    sickle-cell trait

    a genetically inherited recessive condition in which red blood cells are
    distorted resulting in severe anemia and related symptoms that are often fatal in childhood.

  398. assemble

    create by putting components or members together
    Proteins are composed of different combinations of amino acids
    assembled in chain-like molecules.
  399. different

    unlike in nature, quality, form, or degree
    However, because they are
    different, their action may result in
    different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that are the components of proteins.

  400. stand for

    express indirectly by an image, form, or model; be a symbol
    HLA
    stands for "human leukocyte antigen" click this icon to hear the preceding term pronounced.

    homeotic gene click this icon to hear the preceding term pronounced

    see regulator gene.

    homologous chromosomes click this icon to hear the preceding term pronounced

    chromosomes that are paired during the production of of sex cells in meiosis.

  401. surround

    extend on all sides of simultaneously; encircle
    Viruses are not cells but rather RNA or DNA molecules
    surrounded by a protein coating.
  402. reproduction

    the act of making copies
    Sickle-cell trait is also known as sickle-cell anemia.

    somatic cell click this icon to hear the preceding term pronounced

    any cell in the body except those directly involved with
    reproduction.

  403. sequence

    a following of one thing after another in time
    Physically, a gene is a
    sequence of DNA bases that specify the order of amino acids in an entire protein or, in some cases, a portion of a protein.
  404. underlying

    in the nature of something though not readily apparent
    Genetic mechanisms are the
    underlying foundation for evolutionary change.
  405. fatal

    bringing death
    This is ultimately a
    fatal disease, but with modern medical care, about 2/3 of the people with it survive into early adulthood.
  406. migration

    the movement of persons from one locality to another
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    - G -

    gene flow

    the transference of genes from one population to another, usually as a result of
    migration.

  407. category

    a general concept that marks divisions or coordinations
    Back to Top

    - V -

    virus click this icon to hear the preceding term pronounced

    a
    category of extremely small microscopic parasites of plants, animals, and bacteria.

  408. Energy

    the federal department responsible for maintaining a national energy policy of the United States; created in 1977
    Department of
    Energy.
  409. wasting

    any general reduction in vitality and strength of body and mind resulting from a debilitating chronic disease
    MD is characterized by a gradual, irreversible
    wasting of skeletal muscle.
  410. typically

    in a manner conforming to a type
    Children with Angleman syndrome
    typically also have small heads, experience seizures, have pronounced speech impairment, are hyperactive, and have balance disorders.
  411. back

    the posterior part of a human (or animal) body
    Back to Top

    - B -

    blending theory

    an incorrect 19th century theory about the inheritance of characteristics.

  412. affect

    have an influence upon
    He proposed that hereditary particles in the body are
    affected by the things an individual does during his or her lifetime.
  413. propose

    present for consideration, examination, or criticism
    It
    proposed that inherited traits blend from generation to generation.
  414. controlling

    able to control or determine policy
    The genes
    controlling different traits are inherited independently of one another.

    principle of segregation

    Gregor Mendel's first principle of genetic inheritance.

  415. toe

    one of the digits of the foot
    Usually, only one joint is involved, most commonly the base of a big
    toe.
  416. alteration

    the act of revising
    There is no cure for this disorder, and it usually results in death before the age of 30.

    mutation click this icon to hear the preceding term pronounced

    an
    alteration of genetic material such that a new variation is produced.

  417. subsequent

    following in time or order
    The next and
    subsequent generations are referred to as f2, f3, etc.

    fragile-X syndrome click this icon to hear the preceding term pronounced

    a relatively common genetically inherited abnormality of the X chromosome which results in mental retardation.

  418. inability

    lack of capacity to do something
    Back to Top

    - T -

    Tay-Sachs Disease click this icon to hear the preceding term pronounced

    a genetically inherited condition caused by the
    inability to produce the enzyme hexosaminidase A. This results in progressively increased fluid pressure on the brain and the subsequent degeneration of the brain and nervous system beginning about 6 months of age and inevitably resulting in death usually by age 2-3.

  419. Utah

    a state in the western United States
    The idea of a Human Genome Project began at a 1984 international conference in
    Utah.
  420. principle

    a basic generalization that is accepted as true
    Many polygenic traits are also influenced by environmental factors.

    principle of independent assortment

    Gregor Mendel's second
    principle of genetic inheritance.

  421. complex

    complicated in structure
    Simple Mendelian rules of dominance do not apply to the
    complex interaction of these genes.
  422. estimate

    judge tentatively
    In humans, it is
    estimated that each individual possesses approximately 2.9 billion base units in his or her DNA.
  423. make up

    form or compose
    A gene may be
    made up of hundreds of thousands of DNA bases.
  424. normally

    under normal conditions
    MS occurs as a consequence of one's own immune system attacking the insulating sheath that
    normally protects neurons.
  425. chain

    a series of (usually metal) rings or links fitted into one another to make a flexible ligament
    Proteins are composed of different combinations of amino acids assembled in
    chain-like molecules.
  426. swollen

    having an exaggerated sense of self-importance
    Swollen joints caused by internal bleeding is a common problem for hemophiliacs.
  427. are

    a unit of surface area equal to 100 square meters
    However, because they
    are different, their action may result in different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that
    are the components of proteins.

  428. pass

    go across or through
    Carriers often do not show any signs of the trait but can
    pass it on to their offspring.
  429. mid

    used in combination to denote the middle
    The
    mid-range baritone male voice is an example.
  430. code

    a set of rules or principles or laws
    DNA click this icon to hear the preceding term pronounced (deoxyribonucleic acid click this icon to hear the preceding term pronounced)

    a large organic molecule that stores the genetic
    code for the synthesis of proteins.

  431. research

    a seeking for knowledge
    Human Genome Project

    a multinational
    research effort designed to identify and map the location of all human genes.

  432. ratio

    relation with respect to comparative quantity or magnitude
    Probability is usually expressed as the
    ratio of the number of actual occurrences to the number of possible occurrences.

    proteins click this icon to hear the preceding term pronounced

    any of a large number of complex organic molecules that are composed of one or more chains of amino acids.

  433. situation

    physical position in relation to the surroundings
    Humans have 46 chromosomes in each somatic cell and 23 in each sex cell.

    codominance click this icon to hear the preceding term pronounced

    the
    situation in which two different alleles for a trait are expressed unblended in the phenotype of heterozygous individuals.

  434. potential

    existing in possibility
    Punnett square click this icon to hear the preceding term pronounced

    a simple graphical method of showing all of the
    potential combinations of offspring genotypes that can occur and their probability given the parent genotypes.

  435. commonly

    under normal conditions
    Usually, only one joint is involved, most
    commonly the base of a big toe.
  436. system

    a group of independent elements comprising a unified whole
    HLA
    system click this icon to hear the preceding term pronounced

    the body's genetically inherited
    system for recognizing and rejecting foreign tissues, such as transplanted organs.

  437. recipient

    a person who is sent something
    The loss or addition of individuals can easily change the gene pool frequencies of both the
    recipient and donor populations--that is, they can evolve.

    gene pool

    all of the genes in all of the individuals in a breeding population.

  438. combine

    put or add together
    More precisely, this is a cell that is formed when a sperm and an ovum
    combine their chromosomes at conception.
  439. expression

    the communication of your beliefs or opinions
    However, because they are different, their action may result in different
    expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that are the components of proteins.

  440. blood

    the fluid that is pumped through the body by the heart
    Type AB
    blood is an example.
  441. species

    taxonomic group whose members can interbreed
    Such traits are said to be codominant.

    cross-pollination

    the mating of two genetically different plants of the same
    species.

  442. switch

    device for making or breaking the connections in a circuit
    Shortly after conception, regulator genes work as master
    switches orchestrating the timely development of our body parts.
  443. limit

    as far as something can go
    See sex-
    limited gene.

    sex-
    limited gene

    a gene that can be inherited by both genders but is usually expressed in only males or females.

  444. defect

    a failing or deficiency
    It is believed that the lack of abundant sun exposure early in life is somehow responsible for the later onset of MS.

    muscular dystrophy click this icon to hear the preceding term pronounced (MD)

    any of a group of inherited progressive muscle disorders caused by a
    defect in one or more genes that control muscle function.

  445. physically

    in accord with physical laws
    Physically, a gene is a sequence of DNA bases that specify the order of amino acids in an entire protein or, in some cases, a portion of a protein.
  446. reject

    refuse to accept or acknowledge
    HLA system click this icon to hear the preceding term pronounced

    the body's genetically inherited system for recognizing and
    rejecting foreign tissues, such as transplanted organs.

  447. oxygen

    a colorless, odorless gas that is essential for respiration
    Amino acids are primarily composed of carbon,
    oxygen, hydrogen, and nitrogen.
  448. cross

    a marking that consists of lines that intersect each other
    Through his plant
    cross-breeding experiments, Gregor Mendel proved that this was wrong

    Back to Top

    - C -

    carrier

    an individual who is heterozygous for a trait that only shows up in the phenotype of those who are homozygous recessive.

  449. female

    of the sex that produces eggs from which offspring develop
    Approximately 1 in 700
    females are carriers of the gene for this trait.
  450. distribution

    the act of spreading or apportioning
    In other words, the
    distribution of one pair of alleles does not influence the
    distribution of another pair.
  451. member

    anything that belongs to a set or class
    They also have the same genes, but not necessarily the same alleles, at the same locus or location.

    homozygous click this icon to hear the preceding term pronounced

    having the same allele at the same locus on both
    members of a pair of homologous chromosomes.

  452. begin

    set in motion, cause to start
    The idea of a Human Genome Project
    began at a 1984 international conference in Utah.
  453. particular

    unique or specific to a person or thing or category
    Genotype can refer to an organism's entire genetic makeup or the alleles at a
    particular locus.
  454. expose

    show; make visible or apparent
    There is a correlation between the amount of sunlight that children are
    exposed to and the likelihood that they will develop MS later in life.
  455. precisely

    in a sharply exact manner
    More
    precisely, it is the collective genotype of a population.

    genes click this icon to hear the preceding term pronounced

    units of inheritance usually occurring at specific locations, or loci, on a chromosome.

  456. conception

    the creation of something in the mind
    Shortly after
    conception, regulator genes work as master switches orchestrating the timely development of our body parts.
  457. skin

    a natural protective body covering and site of the sense of touch
    albinism click this icon to hear the preceding term pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in
    skin, hair, and eyes.

  458. division

    the act of partitioning
    They are visible only under magnification during certain stages of cell
    division.
  459. depend on

    be contingent on
    See Human Genome Project.

    genome imprinting click this icon to hear the preceding term pronounced

    an inheritance pattern in which a gene will have a different effect
    depending on the gender of the parent from whom it is inherited.

  460. photo

    a representation of a person or scene in the form of a print or transparent slide; recorded by a camera on light-sensitive material
    They may be inherited or caused by diabetes and environmental factors.

    photo of a normal eye and another with a cataract

    chronic disease

    an illness that lasts for a long period of time or indefinitely.

  461. carbon

    an abundant nonmetallic element in all organic compounds
    Amino acids are primarily composed of
    carbon, oxygen, hydrogen, and nitrogen.
  462. govern

    exercise authority over, as of nations
    The alleles for a trait occupy the same locus or position on homologous chromosomes and thus
    govern the same trait.
  463. painfully

    unpleasantly
    Symptoms include
    painfully inflamed joints, especially of the feet and hands, that can become chronic and result in deformity.
  464. large number

    a large indefinite number
    Probability is usually expressed as the ratio of the number of actual occurrences to the number of possible occurrences.

    proteins click this icon to hear the preceding term pronounced

    any of a
    large number of complex organic molecules that are composed of one or more chains of amino acids.

  465. gradual

    proceeding in small stages
    MD is characterized by a
    gradual, irreversible wasting of skeletal muscle.
  466. differently

    in another and different manner
    See somatic cell.

    sex-controlled gene

    a gene that can be inherited by both genders but is usually expressed
    differently in males and females.

  467. Darwin

    English natural scientist who formulated a theory of evolution by natural selection (1809-1882)
    Back to Top

    - P -

    pangenesis click this icon to hear the preceding term pronounced

    Charles
    Darwin's incorrect theory about the inheritance of traits.

  468. theory

    a belief that can guide behavior
    Back to Top

    - B -

    blending
    theory

    an incorrect 19th century
    theory about the inheritance of characteristics.

  469. descendants

    all of the offspring of a given progenitor
    Back to Top

    - U -

    unit inheritance

    Gregor Mendel's idea that the characteristics of parents are passed on to
    descendants unchanged as units.

  470. attacking

    disposed to attack
    MS occurs as a consequence of one's own immune system
    attacking the insulating sheath that normally protects neurons.
  471. in earnest

    in a serious manner
    Research to decode the human genome began
    in earnest in 1986, funded by the U.S.
  472. shaped

    having the shape of
    DNA is composed of sugars, phosphates and bases arranged in a double helix
    shaped molecular structure.
  473. bind

    secure with or as if with ropes
    Proteins can serve a wide variety of functions through their ability to
    bind to other molecules.
  474. modified

    changed in form or character
    These
    modified particles were thought to migrate via blood to the reproductive cells and subsequently could be inherited by the next generation.
  475. doubled

    twice as great or many
    See sex cell.

    sperm click this icon to hear the preceding term pronounced

    a male sex cell or gamete.

    stuttering alleles

    defective alleles that have segments which are
    doubled in their transmission from generation to generation.

  476. structure

    a complex entity made of many parts
    DNA is composed of sugars, phosphates and bases arranged in a double helix shaped molecular
    structure.
  477. 19th

    coming next after the eighteenth in position
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    - B -

    blending theory

    an incorrect
    19th century theory about the inheritance of characteristics.

  478. lifetime

    the period during which something is functional
    He proposed that hereditary particles in the body are affected by the things an individual does during his or her
    lifetime.
  479. leg

    a human limb
    In advanced stages, this often results in blindness from cataracts, nerve damage, gangrene in the feet and
    legs leading to amputation, heart disease, and kidney failure.
  480. phase

    any distinct time period in a sequence of events
    The next
    phase of research will be to identify the proteins for which these genes code.
  481. odds

    the likelihood of a thing occurring
    Punnett squares are commonly used by genetics counselors to predict the
    odds of a couple passing on particular inherited traits.

    illustration of how to set up a Punnett square

    purebred click this icon to hear the preceding term pronounced

    offspring that are the result of mating between genetically similar kinds of parents--the opposite of hybrid.

  482. alter

    cause to change; make different
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be explained by simple rules of dominance and recessiveness of genes.

    modifying gene

    a gene that can
    alter the expression of another gene in the phenotype of an individual.

    monozygotic twins click this icon to hear the preceding term pronounced

    identical twins.

  483. change

    become different in some particular way
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    - E -

    evolution click this icon to hear the preceding term pronounced

    genetic
    change in a population of organisms that occurs over time.

  484. patch

    a small contrasting part of something
    See Human Genome Project.

    psoriasis click this icon to hear the preceding term pronounced

    an inherited disease characterized by recurring thick, reddish
    patches of inflamed skin.

  485. acute

    ending in a sharp point
    In contrast, an
    acute disease is one with a rapid onset and a short but usually severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-carrying bodies in the nucleus of a cell.

  486. exposure

    the state of being vulnerable to something
    It is believed that the lack of abundant sun
    exposure early in life is somehow responsible for the later onset of MS.

    muscular dystrophy click this icon to hear the preceding term pronounced (MD)

    any of a group of inherited progressive muscle disorders caused by a defect in one or more genes that control muscle function.

  487. each

    (used of count nouns) every one considered individually
    Humans have 46 chromosomes in
    each somatic cell and 23 in
    each sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which two different alleles for a trait are expressed unblended in the phenotype of heterozygous individuals.

  488. tropical

    relating to part of the Earth's surface with hot climate
    People who spend much of their first 16 years in
    tropical and subtropical regions of the world are much less likely to develop this disease than those who live in far northern and far southern regions of our planet.
  489. nervous

    of or relating to a system of sensory apparatus
    Multiple-allele series only partly follow simple Mendelian genetics.

    multiple sclerosis click this icon to hear the preceding term pronounced (MS)

    a genetically inherited progressive disease of the central
    nervous system.

  490. elderly

    very old or advanced in years
    Cataracts are common in
    elderly people.
  491. survive

    continue in existence after
    This is ultimately a fatal disease, but with modern medical care, about 2/3 of the people with it
    survive into early adulthood.
  492. prolonged

    relatively long in duration; tediously protracted
    This results in
    prolonged bleeding from even minor cuts and injuries.
  493. cause

    events that provide the generative force of something
    This is the case with hemophilia.

    cataract click this icon to hear the preceding term pronounced

    an impairment of vision
    caused by the lenses of the eyes becoming cloudy.

  494. swell

    increase in size, magnitude, number, or intensity
    Swollen joints caused by internal bleeding is a common problem for hemophiliacs.
  495. initial

    occurring at the beginning
    The
    initial stage of discovering all human DNA codons was completed early in 2001 at a cost of 2.7 billion dollars.
  496. virtually

    in essence or in effect but not in fact
    Differences between monozygotic twins later in life are
    virtually always the result of environmental influences rather than genetic inheritance.
  497. entire

    constituting the full quantity or extent; complete
    Physically, a gene is a sequence of DNA bases that specify the order of amino acids in an
    entire protein or, in some cases, a portion of a protein.
  498. simple

    having few parts; not complex or complicated or involved
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be explained by
    simple rules of dominance and recessiveness of genes.

    modifying gene

    a gene that can alter the expression of another gene in the phenotype of an individual.

    monozygotic twins click this icon to hear the preceding term pronounced

    identical twins.

  499. relate

    give an account of
    See sex-controlled gene.

    sickle-cell trait

    a genetically inherited recessive condition in which red blood cells are distorted resulting in severe anemia and
    related symptoms that are often fatal in childhood.

  500. emotional

    of or pertaining to feelings
    The triggering of genetically inherited diabetes by obesity and possibly severe
    emotional stress is an example.

    intermediate expression

    the situation in which a heterozygous genotype results in a phenotype that is intermediate between those resulting from the homozygous genotypes.

  501. body

    an individual 3-dimensional object that has mass
    In contrast, an acute disease is one with a rapid onset and a short but usually severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-carrying
    bodies in the nucleus of a cell.

  502. increasingly

    advancing in amount or intensity
    In the case of genetically inherited diseases, the result is
    increasingly severe symptoms each generation.
  503. stress

    special emphasis attached to something
    The triggering of genetically inherited diabetes by obesity and possibly severe emotional
    stress is an example.

    intermediate expression

    the situation in which a heterozygous genotype results in a phenotype that is intermediate between those resulting from the homozygous genotypes.

  504. acquire

    come into the possession of something concrete or abstract
    This was a variation of Lamarck's incorrect idea of the "inheritance of
    acquired characteristics."

    phenotype click this icon to hear the preceding term pronounced

    the observable or detectable characteristics of an individual organism--the detectable expression of a genotype.

    pleiotropy click this icon to hear the preceding term pronounced

    the situation in which a single gene is responsible for a variety of traits.

  505. opposite

    being directly across from each other
    In large populations, random deviations in allele frequencies in one direction are more likely to be cancelled out by random changes in the
    opposite direction.

    genetics click this icon to hear the preceding term pronounced

    the study of gene structure and action and the patterns of inheritance of traits from parent to offspring.

  506. square

    a polygon with four equal sides and four right angles
    Punnett
    square click this icon to hear the preceding term pronounced

    a simple graphical method of showing all of the potential combinations of offspring genotypes that can occur and their probability given the parent genotypes.

  507. animal

    a living organism characterized by voluntary movement
    Genes are responsible for the hereditary traits in plants and
    animals.

    genetic drift

    evolution, or change in gene pool frequencies, resulting from random chance.

  508. influence

    a power to affect persons or events
    Neither allele is dominant or recessive, so that both appear in the phenotype or
    influence it.
  509. More

    English statesman who opposed Henry VIII's divorce from Catherine of Aragon and was imprisoned and beheaded; recalled for his concept of Utopia, the ideal state
    More precisely, it is the collective genotype of a population.

    genes click this icon to hear the preceding term pronounced

    units of inheritance usually occurring at specific locations, or loci, on a chromosome.

  510. organs

    edible viscera of a butchered animal
    HLA system click this icon to hear the preceding term pronounced

    the body's genetically inherited system for recognizing and rejecting foreign tissues, such as transplanted
    organs.

  511. involved

    connected by participation or association or use
    Usually, only one joint is
    involved, most commonly the base of a big toe.
  512. sugar

    a white crystalline carbohydrate used as a sweetener
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    - D -

    diabetes click this icon to hear the preceding term pronounced

    an inherited metabolic disorder in which there are abnormally high blood
    sugar levels.

  513. developing

    of societies with low levels of industrial capability
    A zygote contains the full complement of chromosomes (in humans 46) and has the potential of
    developing into an entire organism.
  514. arrange

    put into a proper or systematic order
    DNA is composed of sugars, phosphates and bases
    arranged in a double helix shaped molecular structure.
  515. limited

    subject to constraints
    See sex-
    limited gene.

    sex-
    limited gene

    a gene that can be inherited by both genders but is usually expressed in only males or females.

  516. also

    in addition
    Children with Angleman syndrome typically
    also have small heads, experience seizures, have pronounced speech impairment, are hyperactive, and have balance disorders.
  517. relatively

    by comparison to something else
    The next and subsequent generations are referred to as f2, f3, etc.

    fragile-X syndrome click this icon to hear the preceding term pronounced

    a
    relatively common genetically inherited abnormality of the X chromosome which results in mental retardation.

  518. stage

    any distinct time period in a sequence of events
    They are visible only under magnification during certain
    stages of cell division.
  519. subsequently

    happening at a time later than another time
    These modified particles were thought to migrate via blood to the reproductive cells and
    subsequently could be inherited by the next generation.
  520. chains

    metal shackles; for hands or legs
    Probability is usually expressed as the ratio of the number of actual occurrences to the number of possible occurrences.

    proteins click this icon to hear the preceding term pronounced

    any of a large number of complex organic molecules that are composed of one or more
    chains of amino acids.

  521. same

    same in identity
    The alleles for a trait occupy the
    same locus or position on homologous chromosomes and thus govern the
    same trait.
  522. breathe

    draw air into, and expel out of, the lungs
    Usually, the term is used in reference to the crossing of two pure breeding (homozygous) plants.

    cystic fibrosis click this icon to hear the preceding term pronounced

    a genetically inherited disease in children that results in chronic fluid development in the lungs, making
    breathing difficult.

  523. common

    having no special distinction or quality
    Cataracts are
    common in elderly people.
  524. abundant

    present in great quantity
    It is believed that the lack of
    abundant sun exposure early in life is somehow responsible for the later onset of MS.

    muscular dystrophy click this icon to hear the preceding term pronounced (MD)

    any of a group of inherited progressive muscle disorders caused by a defect in one or more genes that control muscle function.

  525. essentially

    at bottom or by something's very nature
    Twins that come from the same zygote are
    essentially the same genetically.
  526. separate

    standing apart; not attached to or supported by anything
    It states that, for any particular trait, the pair of genes of each parent
    separate (during the formation of sex cells) and only one gene from each parent passes on to an offspring.
  527. thread

    a fine cord of twisted fibers used in sewing and weaving
    In contrast, an acute disease is one with a rapid onset and a short but usually severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-carrying bodies in the nucleus of a cell.

  528. sunlight

    the rays of the sun
    There is a correlation between the amount of
    sunlight that children are exposed to and the likelihood that they will develop MS later in life.
  529. form

    a perceptual structure
    This is a pleiotropic trait.

    alleles click this icon to hear the preceding term pronounced

    alternate
    forms or varieties of a gene.

  530. transport

    move something or somebody around
    Proteins may be enzymes, hormones, antibodies, structural components, or gas-
    transporting molecules.

    proteome click this icon to hear the preceding term pronounced

    the full complement of proteins produced by an individual (or a species).

  531. chemical

    produced by reactions involving atomic or molecular changes
    Regulator genes control the timing of production of a variety of
    chemicals in humans and other organisms.
  532. mental

    involving the mind or an intellectual process
    Angelman syndrome click this icon to hear the preceding term pronounced

    a rare genetically inherited form of
    mental retardation due to the deletion or inactivation of specific genes on chromosome 15.

  533. planet

    a celestial body that revolves around the sun
    People who spend much of their first 16 years in tropical and subtropical regions of the world are much less likely to develop this disease than those who live in far northern and far southern regions of our
    planet.
  534. occupy

    live in (a certain place)
    The alleles for a trait
    occupy the same locus or position on homologous chromosomes and thus govern the same trait.
  535. loss

    the act of losing someone or something
    The
    loss or addition of individuals can easily change the gene pool frequencies of both the recipient and donor populations--that is, they can evolve.

    gene pool

    all of the genes in all of the individuals in a breeding population.

  536. series

    similar things placed in order or one after another
    The HLA system has the most genes of any other known human multiple-allele
    series.
  537. organ

    a structure in an animal specialized for some function
    HLA system click this icon to hear the preceding term pronounced

    the body's genetically inherited system for recognizing and rejecting foreign tissues, such as transplanted
    organs.

  538. age

    how long something has existed
    The symptoms usually do not appear until early middle
    age.
  539. ultimately

    as the end result of a succession or process
    This is
    ultimately a fatal disease, but with modern medical care, about 2/3 of the people with it survive into early adulthood.
  540. formation

    the act of establishing or creating something
    It states that, for any particular trait, the pair of genes of each parent separate (during the
    formation of sex cells) and only one gene from each parent passes on to an offspring.
  541. region

    the extended spatial location of something
    People who spend much of their first 16 years in tropical and subtropical
    regions of the world are much less likely to develop this disease than those who live in far northern and far southern
    regions of our planet.
  542. can

    airtight sealed metal container for food or drink, etc.
    Carriers often do not show any signs of the trait but
    can pass it on to their offspring.
  543. restore

    bring back into original existence, function, or position
    During fertilization, the full number of chromosomes is
    restored, and members of gene pairs are reunited.

    probability

    the likelihood that a specific event will occur.

  544. range

    a variety of different things or activities
    The mid-
    range baritone male voice is an example.
  545. legs

    staying power
    In advanced stages, this often results in blindness from cataracts, nerve damage, gangrene in the feet and
    legs leading to amputation, heart disease, and kidney failure.
  546. due

    that which is deserved or owed
    Angelman syndrome click this icon to hear the preceding term pronounced

    a rare genetically inherited form of mental retardation
    due to the deletion or inactivation of specific genes on chromosome 15.

  547. strictly

    in a stringent manner
    Since viruses cannot reproduce without a host cell, they are not
    strictly speaking living organisms.
  548. appear

    come into sight or view
    Neither allele is dominant or recessive, so that both
    appear in the phenotype or influence it.
  549. motor

    machine that creates mechanical energy and imparts movement
    There is a loss of
    motor and cognitive functions.
  550. often

    many times at short intervals
    Carriers
    often do not show any signs of the trait but can pass it on to their offspring.
  551. brain

    the center of the nervous system
    Back to Top

    - T -

    Tay-Sachs Disease click this icon to hear the preceding term pronounced

    a genetically inherited condition caused by the inability to produce the enzyme hexosaminidase A. This results in progressively increased fluid pressure on the
    brain and the subsequent degeneration of the
    brain and nervous system beginning about 6 months of age and inevitably resulting in death usually by age 2-3.

  552. double

    consisting of or involving two parts or components usually in pairs
    DNA is composed of sugars, phosphates and bases arranged in a
    double helix shaped molecular structure.
  553. condition

    a mode of being or form of existence of a person or thing
    albinism click this icon to hear the preceding term pronounced

    the genetically inherited
    condition in which there is a marked deficiency of pigmentation in skin, hair, and eyes.

  554. breathing

    the bodily process of inhalation and exhalation
    Usually, the term is used in reference to the crossing of two pure breeding (homozygous) plants.

    cystic fibrosis click this icon to hear the preceding term pronounced

    a genetically inherited disease in children that results in chronic fluid development in the lungs, making
    breathing difficult.

  555. possibly

    to a degree possible of achievement or by possible means
    The triggering of genetically inherited diabetes by obesity and
    possibly severe emotional stress is an example.

    intermediate expression

    the situation in which a heterozygous genotype results in a phenotype that is intermediate between those resulting from the homozygous genotypes.

  556. number

    a concept of quantity involving zero and units
    Meiosis involves two divisions and results in four daughter cells, each containing only half the original
    number of chromosomes--23 in the case of humans.
  557. likely

    having a good chance of being the case or of coming about
    It is
    likely to occur 1 in 1000 births.
  558. see

    perceive by sight or have the power to perceive by sight
    See Human Genome Project.

    genome imprinting click this icon to hear the preceding term pronounced

    an inheritance pattern in which a gene will have a different effect depending on the gender of the parent from whom it is inherited.

  559. determine

    find out or learn with certainty, as by making an inquiry
    The collective group of symptoms known as sickle-cell trait is an example.

    polygenic trait click this icon to hear the preceding term pronounced

    an inherited trait that is
    determined by genes at two or more loci.

  560. illness

    impairment of normal physiological function affecting part or all of an organism
    They may be inherited or caused by diabetes and environmental factors.

    photo of a normal eye and another with a cataract

    chronic disease

    an
    illness that lasts for a long period of time or indefinitely.

  561. balance

    harmonious arrangement or relation of parts within a whole
    Children with Angleman syndrome typically also have small heads, experience seizures, have pronounced speech impairment, are hyperactive, and have
    balance disorders.
  562. increased

    made greater in size or amount or degree
    Type 2 diabetes melitis is due to
    increased resistance of cells in the body to insulin.
  563. illustration

    a visual representation to make a subject easy to understand
    Punnett squares are commonly used by genetics counselors to predict the odds of a couple passing on particular inherited traits.

    illustration of how to set up a Punnett square

    purebred click this icon to hear the preceding term pronounced

    offspring that are the result of mating between genetically similar kinds of parents--the opposite of hybrid.

  564. increase

    a process of becoming larger or longer or more numerous
    Type 2 diabetes melitis is due to
    increased resistance of cells in the body to insulin.
  565. development

    a process in which something passes to a different stage
    Usually, the term is used in reference to the crossing of two pure breeding (homozygous) plants.

    cystic fibrosis click this icon to hear the preceding term pronounced

    a genetically inherited disease in children that results in chronic fluid
    development in the lungs, making breathing difficult.

  566. damage

    the occurrence of a change for the worse
    In advanced stages, this often results in blindness from cataracts, nerve
    damage, gangrene in the feet and legs leading to amputation, heart disease, and kidney failure.
  567. experiment

    the act of conducting a controlled test or investigation
    Through his plant cross-breeding
    experiments, Gregor Mendel proved that this was wrong

    Back to Top

    - C -

    carrier

    an individual who is heterozygous for a trait that only shows up in the phenotype of those who are homozygous recessive.

  568. cure

    a medicine or therapy that treats disease or relieves pain
    There is no
    cure for this disorder, and it usually results in death before the age of 30.

    mutation click this icon to hear the preceding term pronounced

    an alteration of genetic material such that a new variation is produced.

  569. known

    apprehended with certainty
    Genome imprinting is also
    known as genetic imprinting.

    genotype click this icon to hear the preceding term pronounced

    the genetic makeup of an individual.

  570. material

    the substance that goes into the makeup of a physical object
    There is no cure for this disorder, and it usually results in death before the age of 30.

    mutation click this icon to hear the preceding term pronounced

    an alteration of genetic
    material such that a new variation is produced.

  571. internal

    located inward
    Swollen joints caused by
    internal bleeding is a common problem for hemophiliacs.
  572. environment

    the totality of surrounding conditions
    Back to Top

    - I -

    incomplete penetrance

    the situation in which an allele is expressed only if certain factors are present in the
    environment.

  573. childhood

    the state of a child between infancy and adolescence
    See sex-controlled gene.

    sickle-cell trait

    a genetically inherited recessive condition in which red blood cells are distorted resulting in severe anemia and related symptoms that are often fatal in
    childhood.

  574. recognize

    perceive to be something or something you can identify
    HLA system click this icon to hear the preceding term pronounced

    the body's genetically inherited system for
    recognizing and rejecting foreign tissues, such as transplanted organs.

  575. of age

    having attained a specific age;
    Back to Top

    - T -

    Tay-Sachs Disease click this icon to hear the preceding term pronounced

    a genetically inherited condition caused by the inability to produce the enzyme hexosaminidase A. This results in progressively increased fluid pressure on the brain and the subsequent degeneration of the brain and nervous system beginning about 6 months
    of age and inevitably resulting in death usually by age 2-3.

  576. depend

    be contingent upon
    See Human Genome Project.

    genome imprinting click this icon to hear the preceding term pronounced

    an inheritance pattern in which a gene will have a different effect
    depending on the gender of the parent from whom it is inherited.

  577. crossing

    a point where two lines (paths or arcs etc.) intersect
    Usually, the term is used in reference to the
    crossing of two pure breeding (homozygous) plants.

    cystic fibrosis click this icon to hear the preceding term pronounced

    a genetically inherited disease in children that results in chronic fluid development in the lungs, making breathing difficult.

  578. host

    a person who invites guests to a social event
    Since viruses cannot reproduce without a
    host cell, they are not strictly speaking living organisms.
  579. map

    a diagrammatic representation of the earth's surface
    Human Genome Project

    a multinational research effort designed to identify and
    map the location of all human genes.

  580. apply

    employ for a particular purpose
    Simple Mendelian rules of dominance do not
    apply to the complex interaction of these genes.
  581. early

    at or near the beginning of a period of time or course of events or before the usual or expected time
    This is ultimately a fatal disease, but with modern medical care, about 2/3 of the people with it survive into
    early adulthood.
  582. necessarily

    in such a manner as could not be otherwise
    They also have the same genes, but not
    necessarily the same alleles, at the same locus or location.

    homozygous click this icon to hear the preceding term pronounced

    having the same allele at the same locus on both members of a pair of homologous chromosomes.

  583. minor

    inferior in number or size or amount
    This results in prolonged bleeding from even
    minor cuts and injuries.
  584. flow

    move along, of liquids
    Back to Top

    - G -

    gene
    flow

    the transference of genes from one population to another, usually as a result of migration.

  585. contrast

    the opposition or dissimilarity of things that are compared
    In
    contrast, an acute disease is one with a rapid onset and a short but usually severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-carrying bodies in the nucleus of a cell.

  586. death

    the permanent end of all life functions in an organism
    There is a progressive loss of muscle control that inevitably leads to paralysis and
    death.
  587. passing

    lasting a very short time
    The most common form, Duchene MD, begins to weaken the legs of boys by age 3 and inevitably gets worse with each
    passing year.
  588. show

    make visible or noticeable
    Since the gene for albinism is recessive, it only
    shows up in the phenotype of homozygous recessive people.
  589. eye

    the organ of sight
    albinism click this icon to hear the preceding term pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin, hair, and
    eyes.

  590. original

    preceding all others in time
    This decoding of the human proteome will be an even more daunting task than the
    original Human Genome Project.
  591. designed

    done or made or performed with purpose and intent
    Human Genome Project

    a multinational research effort
    designed to identify and map the location of all human genes.

  592. resistance

    any mechanical force that tends to slow or oppose motion
    Type 2 diabetes melitis is due to increased
    resistance of cells in the body to insulin.
  593. fund

    a reserve of money set aside for some purpose
    Research to decode the human genome began in earnest in 1986,
    funded by the U.S.
  594. rule

    prescribed guide for conduct or action
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be explained by simple
    rules of dominance and recessiveness of genes.

    modifying gene

    a gene that can alter the expression of another gene in the phenotype of an individual.

    monozygotic twins click this icon to hear the preceding term pronounced

    identical twins.

  595. dollar

    the basic monetary unit in many countries
    The initial stage of discovering all human DNA codons was completed early in 2001 at a cost of 2.7 billion
    dollars.
  596. exposed

    with no protection or shield
    There is a correlation between the amount of sunlight that children are
    exposed to and the likelihood that they will develop MS later in life.
  597. billion

    one thousand million items or units in the United States
    In humans, it is estimated that each individual possesses approximately 2.9
    billion base units in his or her DNA.
  598. injury

    physical damage to the body caused by violence or accident
    This results in prolonged bleeding from even minor cuts and
    injuries.
  599. set up

    create by putting components or members together
    Punnett squares are commonly used by genetics counselors to predict the odds of a couple passing on particular inherited traits.

    illustration of how to
    set up a Punnett square

    purebred click this icon to hear the preceding term pronounced

    offspring that are the result of mating between genetically similar kinds of parents--the opposite of hybrid.

  600. similar

    having the same or nearly the same characteristics
    Fraternal twins may look
    similar but are not genetically identical.

    multiple-allele series click this icon to hear the preceding term pronounced

    a situation in which a gene has more than two alleles.

  601. acquired

    gotten through environmental forces
    This was a variation of Lamarck's incorrect idea of the "inheritance of
    acquired characteristics."

    phenotype click this icon to hear the preceding term pronounced

    the observable or detectable characteristics of an individual organism--the detectable expression of a genotype.

    pleiotropy click this icon to hear the preceding term pronounced

    the situation in which a single gene is responsible for a variety of traits.

  602. possess

    have ownership of
    In humans, it is estimated that each individual
    possesses approximately 2.9 billion base units in his or her DNA.
  603. both

    (used with count nouns) two considered together; the two
    Neither allele is dominant or recessive, so that
    both appear in the phenotype or influence it.
  604. live in

    live in the house where one works
    People who spend much of their first 16 years in tropical and subtropical regions of the world are much less likely to develop this disease than those who
    live in far northern and far southern regions of our planet.
  605. include

    have as a part; be made up out of
    Symptoms
    include painfully inflamed joints, especially of the feet and hands, that can become chronic and result in deformity.
  606. completed

    successfully completed or brought to an end
    The initial stage of discovering all human DNA codons was
    completed early in 2001 at a cost of 2.7 billion dollars.
  607. late

    at or toward an end or late period or stage of development
    Differences between monozygotic twins
    later in life are virtually always the result of environmental influences rather than genetic inheritance.
  608. northern

    situated in or oriented toward the north
    People who spend much of their first 16 years in tropical and subtropical regions of the world are much less likely to develop this disease than those who live in far
    northern and far southern regions of our planet.
  609. alike

    having the same or similar characteristics
    Such chromosomes are
    alike with regard to size and also position of the centromere.
  610. block

    obstruct
    Recessive alleles are expressed in the phenotype when the genotype is homozygous recessive (aa).

    regulator gene

    a gene that can initiate or
    block the functions of other genes.

  611. idea

    the content of cognition
    The
    idea of a Human Genome Project began at a 1984 international conference in Utah.
  612. direction

    a line leading to a place or point
    In large populations, random deviations in allele frequencies in one
    direction are more likely to be cancelled out by random changes in the opposite
    direction.

    genetics click this icon to hear the preceding term pronounced

    the study of gene structure and action and the patterns of inheritance of traits from parent to offspring.

  613. apparent

    clearly revealed to the mind or the senses or judgment
    As a result, phenotypes may appear as
    apparent blends or intermediate expressions.
  614. shortly

    in the near future
    Shortly after conception, regulator genes work as master switches orchestrating the timely development of our body parts.
  615. protect

    shield from danger, injury, destruction, or damage
    MS occurs as a consequence of one's own immune system attacking the insulating sheath that normally
    protects neurons.
  616. most

    quantifier meaning the greatest in number
    Most fragile-X males have large testes, big ears, narrow faces, and sensory integration dysfunctions that result in learning disabilities.
  617. case

    an occurrence of something
    This is the
    case with hemophilia.

    cataract click this icon to hear the preceding term pronounced

    an impairment of vision caused by the lenses of the eyes becoming cloudy.

  618. rapid

    characterized by speed
    In contrast, an acute disease is one with a
    rapid onset and a short but usually severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-carrying bodies in the nucleus of a cell.

  619. reference

    the act of consulting
    Usually, the term is used in
    reference to the crossing of two pure breeding (homozygous) plants.

    cystic fibrosis click this icon to hear the preceding term pronounced

    a genetically inherited disease in children that results in chronic fluid development in the lungs, making breathing difficult.

  620. shape

    a perceptual structure
    DNA is composed of sugars, phosphates and bases arranged in a double helix
    shaped molecular structure.
  621. discover

    determine the existence, presence, or fact of
    The initial stage of
    discovering all human DNA codons was completed early in 2001 at a cost of 2.7 billion dollars.
  622. foundation

    the basis on which something is grounded
    Genetic mechanisms are the underlying
    foundation for evolutionary change.
  623. carry

    physically move while supporting, by vehicle, hands, or body
    In contrast, an acute disease is one with a rapid onset and a short but usually severe course.

    chromosomes click this icon to hear the preceding term pronounced

    thread-like, gene-
    carrying bodies in the nucleus of a cell.

  624. full

    containing as much or as many as is possible or normal
    Genetics is the branch of science that deals with the inheritance of biological characteristics.

    genome click this icon to hear the preceding term pronounced

    the
    full genetic complement of an individual (or of a species).

  625. international

    concerning or belonging to two or more countries
    The idea of a Human Genome Project began at a 1984
    international conference in Utah.
  626. only

    without any others being included or involved
    Since the gene for albinism is recessive, it
    only shows up in the phenotype of homozygous recessive people.
  627. waste

    use inefficiently or inappropriately
    MD is characterized by a gradual, irreversible
    wasting of skeletal muscle.
  628. related

    connected logically or causally or by shared characteristics
    See sex-controlled gene.

    sickle-cell trait

    a genetically inherited recessive condition in which red blood cells are distorted resulting in severe anemia and
    related symptoms that are often fatal in childhood.

  629. earnest

    characterized by a firm, humorless belief in one's opinions
    Research to decode the human genome began in
    earnest in 1986, funded by the U.S.
  630. affected

    influenced
    He proposed that hereditary particles in the body are
    affected by the things an individual does during his or her lifetime.
  631. presence

    current existence
    The gene or genes for diabetes are incompletely penetrant.

    dominant allele

    an allele that masks the
    presence of a recessive allele in the phenotype.

  632. call

    utter a sudden loud cry
    This disease is also
    called Huntington's chorea click this icon to hear the preceding term pronounced.

    hybrids click this icon to hear the preceding term pronounced

    offspring that are the result of mating between two genetically different kinds of parents--the opposite of purebred.

  633. mark

    a distinguishing symbol
    albinism click this icon to hear the preceding term pronounced

    the genetically inherited condition in which there is a
    marked deficiency of pigmentation in skin, hair, and eyes.

  634. large

    above average in size or number or quantity or magnitude
    DNA click this icon to hear the preceding term pronounced (deoxyribonucleic acid click this icon to hear the preceding term pronounced)

    a
    large organic molecule that stores the genetic code for the synthesis of proteins.

  635. lead

    take somebody somewhere
    In advanced stages, this often results in blindness from cataracts, nerve damage, gangrene in the feet and legs
    leading to amputation, heart disease, and kidney failure.
  636. word

    a unit of language that native speakers can identify
    In other
    words, the distribution of one pair of alleles does not influence the distribution of another pair.
  637. live

    have life, be alive
    There are 20 different kinds of amino acids in
    living things.
  638. ability

    the quality of having the means or skills to do something
    Proteins can serve a wide variety of functions through their
    ability to bind to other molecules.
  639. somehow

    in some unspecified way or manner
    It is believed that the lack of abundant sun exposure early in life is
    somehow responsible for the later onset of MS.

    muscular dystrophy click this icon to hear the preceding term pronounced (MD)

    any of a group of inherited progressive muscle disorders caused by a defect in one or more genes that control muscle function.

  640. visible

    capable of being seen or open to easy view
    They are
    visible only under magnification during certain stages of cell division.
  641. extremely

    to the greatest possible degree
    Back to Top

    - V -

    virus click this icon to hear the preceding term pronounced

    a category of
    extremely small microscopic parasites of plants, animals, and bacteria.

  642. for instance

    as an example
    For instance, a trait that has only one allele (A) can mutate to a new form (a).
  643. failure

    an act that does not succeed
    In advanced stages, this often results in blindness from cataracts, nerve damage, gangrene in the feet and legs leading to amputation, heart disease, and kidney
    failure.
  644. branch

    a division of a stem arising from the main stem of a plant
    Genetics is the
    branch of science that deals with the inheritance of biological characteristics.

    genome click this icon to hear the preceding term pronounced

    the full genetic complement of an individual (or of a species).

  645. arranged

    disposed or placed in a particular kind of order
    DNA is composed of sugars, phosphates and bases
    arranged in a double helix shaped molecular structure.
  646. possible

    capable of happening or existing
    There are at least 30,000,000
    possible HLA genotypes.
  647. foot

    the pedal extremity of vertebrates other than human beings
    In advanced stages, this often results in blindness from cataracts, nerve damage, gangrene in the
    feet and legs leading to amputation, heart disease, and kidney failure.
  648. gas

    state of matter distinguished from solid and liquid states
    Proteins may be enzymes, hormones, antibodies, structural components, or
    gas-transporting molecules.

    proteome click this icon to hear the preceding term pronounced

    the full complement of proteins produced by an individual (or a species).

  649. surrounded

    confined on all sides
    Viruses are not cells but rather RNA or DNA molecules
    surrounded by a protein coating.
  650. fat

    a soft greasy substance occurring in organic tissue
    This disease also prevents normal absorption of
    fats and other nutrients from food.
  651. addition

    the arithmetic operation of summing
    The loss or
    addition of individuals can easily change the gene pool frequencies of both the recipient and donor populations--that is, they can evolve.

    gene pool

    all of the genes in all of the individuals in a breeding population.

  652. later

    happening at a time subsequent to a reference time
    Differences between monozygotic twins
    later in life are virtually always the result of environmental influences rather than genetic inheritance.
  653. actual

    existing in act or fact
    Probability is usually expressed as the ratio of the number of
    actual occurrences to the number of possible occurrences.

    proteins click this icon to hear the preceding term pronounced

    any of a large number of complex organic molecules that are composed of one or more chains of amino acids.

  654. independent

    free from external control and constraint
    Many polygenic traits are also influenced by environmental factors.

    principle of
    independent assortment

    Gregor Mendel's second principle of genetic inheritance.

  655. learning

    the cognitive process of acquiring skill or knowledge
    Most fragile-X males have large testes, big ears, narrow faces, and sensory integration dysfunctions that result in
    learning disabilities.
  656. vision

    the ability to see
    This is the case with hemophilia.

    cataract click this icon to hear the preceding term pronounced

    an impairment of
    vision caused by the lenses of the eyes becoming cloudy.

  657. between

    in the interval
    This disease is also called Huntington's chorea click this icon to hear the preceding term pronounced.

    hybrids click this icon to hear the preceding term pronounced

    offspring that are the result of mating
    between two genetically different kinds of parents--the opposite of purebred.

  658. lack

    the state of needing something that is absent or unavailable
    It is believed that the
    lack of abundant sun exposure early in life is somehow responsible for the later onset of MS.

    muscular dystrophy click this icon to hear the preceding term pronounced (MD)

    any of a group of inherited progressive muscle disorders caused by a defect in one or more genes that control muscle function.

  659. small

    limited or below average in number or quantity or magnitude
    However, because they are different, their action may result in different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that are the components of proteins.

  660. medical

    relating to the study or practice of medicine
    This is ultimately a fatal disease, but with modern
    medical care, about 2/3 of the people with it survive into early adulthood.
  661. design

    the act of working out the form of something
    Human Genome Project

    a multinational research effort
    designed to identify and map the location of all human genes.

  662. two

    the cardinal number that is the sum of one and one
    Humans have 46 chromosomes in each somatic cell and 23 in each sex cell.

    codominance click this icon to hear the preceding term pronounced

    the situation in which
    two different alleles for a trait are expressed unblended in the phenotype of heterozygous individuals.

  663. build

    make by combining materials and parts
    See phenotype.

    gout click this icon to hear the preceding term pronounced

    a genetically inherited metabolic disorder in which there is an imbalance of uric acid in the blood which causes a
    build up of urates in joint areas.

  664. group

    any number of entities (members) considered as a unit
    It is believed that the lack of abundant sun exposure early in life is somehow responsible for the later onset of MS.

    muscular dystrophy click this icon to hear the preceding term pronounced (MD)

    any of a
    group of inherited progressive muscle disorders caused by a defect in one or more genes that control muscle function.

  665. spend

    pass time in a specific way
    People who
    spend much of their first 16 years in tropical and subtropical regions of the world are much less likely to develop this disease than those who live in far northern and far southern regions of our planet.
  666. hair

    a covering for the body (or parts of it) consisting of a dense growth of threadlike structures (as on the human head); helps to prevent heat loss
    albinism click this icon to hear the preceding term pronounced

    the genetically inherited condition in which there is a marked deficiency of pigmentation in skin,
    hair, and eyes.

  667. conference

    a prearranged meeting for consultation or discussion
    The idea of a Human Genome Project began at a 1984 international
    conference in Utah.
  668. eastern

    lying toward or situated in the east
    It has been most common among the descendents of
    Eastern European Jews (Ashkenazi Jews).

    true breeding

    see purebred.

  669. rare

    especially good, remarkable, or superlative
    Angelman syndrome click this icon to hear the preceding term pronounced

    a
    rare genetically inherited form of mental retardation due to the deletion or inactivation of specific genes on chromosome 15.

  670. new

    not of long duration
    The term is also frequently used to refer to the appearance of a
    new species.
  671. child

    a human offspring (son or daughter) of any age
    Children with Angleman syndrome typically also have small heads, experience seizures, have pronounced speech impairment, are hyperactive, and have balance disorders.
  672. becoming

    displaying or setting off to best advantage
    This is the case with hemophilia.

    cataract click this icon to hear the preceding term pronounced

    an impairment of vision caused by the lenses of the eyes
    becoming cloudy.

  673. action

    something done (usually as opposed to something said)
    However, because they are different, their
    action may result in different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that are the components of proteins.

  674. consequence

    a phenomenon that is caused by some previous phenomenon
    MS occurs as a
    consequence of one's own immune system attacking the insulating sheath that normally protects neurons.
  675. partly

    in part; in some degree; not wholly
    Multiple-allele series only
    partly follow simple Mendelian genetics.

    multiple sclerosis click this icon to hear the preceding term pronounced (MS)

    a genetically inherited progressive disease of the central nervous system.

  676. coat

    an outer garment that covers the body from shoulder down
    Viruses are not cells but rather RNA or DNA molecules surrounded by a protein
    coating.
  677. older

    advanced in years; (`aged' is pronounced as two syllables)
    They are also responsible for changes that occur in our bodies as we grow
    older.
  678. store

    a mercantile establishment for the sale of goods or services
    DNA click this icon to hear the preceding term pronounced (deoxyribonucleic acid click this icon to hear the preceding term pronounced)

    a large organic molecule that
    stores the genetic code for the synthesis of proteins.

  679. pressure

    the exertion of force to a surface
    Back to Top

    - T -

    Tay-Sachs Disease click this icon to hear the preceding term pronounced

    a genetically inherited condition caused by the inability to produce the enzyme hexosaminidase A. This results in progressively increased fluid
    pressure on the brain and the subsequent degeneration of the brain and nervous system beginning about 6 months of age and inevitably resulting in death usually by age 2-3.

  680. other

    not the same one or ones already mentioned or implied
    This disease also prevents normal absorption of fats and
    other nutrients from food.
  681. may

    thorny shrub of a small tree having white to scarlet flowers
    However, because they are different, their action
    may result in different expressions of that trait.

    amino acids click this icon to hear the preceding term pronounced

    small molecules that are the components of proteins.

  682. showing

    the display of a motion picture
    Punnett square click this icon to hear the preceding term pronounced

    a simple graphical method of
    showing all of the potential combinations of offspring genotypes that can occur and their probability given the parent genotypes.

  683. color

    a visual attribute of things from the light they emit
    Human skin and hair
    color are polygenic traits.
  684. explain

    make plain and comprehensible
    Mendelian genetics click this icon to hear the preceding term pronounced

    inheritance patterns which can be
    explained by simple rules of dominance and recessiveness of genes.

    modifying gene

    a gene that can alter the expression of another gene in the phenotype of an individual.

    monozygotic twins click this icon to hear the preceding term pronounced

    identical twins.

  685. another

    any of various alternatives; some other
    They may be inherited or caused by diabetes and environmental factors.

    photo of a normal eye and
    another with a cataract

    chronic disease

    an illness that lasts for a long period of time or indefinitely.

  686. method

    a way of doing something, especially a systematic way
    Punnett square click this icon to hear the preceding term pronounced

    a simple graphical
    method of showing all of the potential combinations of offspring genotypes that can occur and their probability given the parent genotypes.

  687. neither

    not either; not one or the other
    Neither allele is dominant or recessive, so that both appear in the phenotype or influence it.
  688. area

    the extent of a two-dimensional surface within a boundary
    See phenotype.

    gout click this icon to hear the preceding term pronounced

    a genetically inherited metabolic disorder in which there is an imbalance of uric acid in the blood which causes a build up of urates in joint
    areas.

  689. kind

    having a tender and considerate and helpful nature
    There are 20 different
    kinds of amino acids in living things.
  690. rapidly

    with quick movements
    Genetic drift occurs most
    rapidly in small populations.
  691. living

    pertaining to living persons
    There are 20 different kinds of amino acids in
    living things.
Created on April 25, 2013

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