Card Set Information

2014-03-20 19:15:18

Show Answers:

  1. What is genetics?
    the study of inheritance or inherited traits
  2. What did Mendel work with?
    Garden peas
  3. Define GENOTYPE
    the alleles carried by an individual. Bb will have brown eyes, but so will BB. Bb is the genotype. Brown eyes is the phenotype.
  4. Define PHENOTYPE
    An individual’s observable traits.
  5. Allele
    Forms of a gene that encode slightly different versions of the gene’s product; different forms of the same gene; different instructions for the same trait
  6. Dominant allele
    Refers to an allele that masks the effect of a recessive allele paired with it... in other words it's trait is expressed even when only one is present. Bb= brown eyes. Always.
  7. Trait
    the character for which a gene carries instructions: hair color, eye color, etc
  8. Gene
    • –Region of chromosome with the
    • instructions for a specific trait

    • –Remember you have two sets of
    • genes for every trait

    •That is, genes come in pairs
  9. Homozygous
    zygotes have same two alleles—homozygous
  10. heterozygous
    zygotes have two different alleles
  11. recessive
    a trait that is only expressed if both alleles are recessive. bb= blue eyes. only.
  12. Homozygous dominant example
  13. Homozygous Recessive example
  14. Heterozygous example
  15. Monohybrid cross
    Cross in which individuals with different alleles of one gene are crossed.
  16. Single trait inheritance
    Means there is a dominant gene that will show if presented, one gene pair controls the trait.
  17. Testcross
    When you try to cross parental gametes to see if possible children will have certain traits
  18. Incomplete dominance
    When a trait doesn't have a dominant gene, such as hair texture
  19. Multiple allele inheritance
    traits that have more than two alleles controlling them, and some with more than one dominant alleles. Blood type has three alleles with two dominant and one recessive
  20. Codominant
    Refers to two alleles that are both fully expressed in heterozygous individuals. Blood type is co-dominant
  21. Polygenic inheritance
    Many sets of genes effect a single trait. Example, human skin color
  22. Epistasis
    Two genes control a single trait. In other words, one gene controls the expression of a 2nd gene. Example: Labrador coat color
  23. Pleiotropy
    One gene effects many traits, like people with Marfan sydrome (one gene) people are tall and thin with long arms and long legs, and long fingers
  24. Gene environment interaction
    Expression of the gene depends on the surrounding environment. Examples; snowshoe hare's coat turns darker when it warms up. Siamese cat coat turns darker where they are colder (extremities and tips of ears)
  25. Brown eyes: dominant or recessive?
    Dominant. Blue is the recessive eye color trait. B (brown) b (blue)
  26. Tongue rolling; dominant or recessive
    Dominant. U (roll) u (can't roll)
  27. Mendel's law of segregation
    allele pairs separate or segregate during gamete formation, and randomly unite at fertilization
  28. What parent is solely responsible for the sex of the child?
    The father. The mother can only give X's. Father gives X or Y determining the sex.
  29. Polyploidy
    Having three or more of each type of chromosome characteristic of the species. Common in plants. Humans with polyploidy generally don't make it to full term
  30. Autosomal recessive disorder
    Recessive allele on an autosome causes a disorder. Examples: Sickle cell anemia and Cystic fibrosis, albinism, PKU Tay-sachs. Aa is normal but a carrier. AA is normal. aa is affected.
  31. Autosomal dominant disorder
    Dominant allele carries the disorder. AA or Aa has the disorder. aa is normal. Examples: hypercholesterolemia, dwarfism, polydactyly (more than normal number of fingers or toes)
  32. Aneuploidy
    inheriting too few or too many chromosomes, caused by nondisjunction of chromosomes during meiosis ii. Example: Down's syndrome
  33. Nondisjunction
    When sisters fail to separate in meiosis II, or homologous chromosomes fail to separate in meiosis I. It can result in Down's Syndrome, too many chromosomes in a sperm cell, too few chromosomes in an egg cell, aneuploidy
  34. Cause of Down's Syndrome
    Three copies of chromosome 21, aneuploidy, and nondisjunction occurring from meiosis
  35. Types of genetic disorders by chromosomal mutation
    • Inversion
    • Translocation
    • Deletion
    • Duplication
  36. Inversion
  37. Translocation
  38. Deletion
    ABCDEFGH------->ABC  FGH
  39. Duplication
  40. What is Turner Syndrome?
    A sex chromosome problem. Only a Single X is inherited, no second chromosome
  41. What is Klinefelter syndrome?
    Too many sex chromosomes XXY, produces sterile men with small breasts
  42. Triple X Female
    Metafemale, superfemale, inherited 3 x's no visible difference to the naked eye
  43. Colorblindness
  44. How can genes be mutates?
    Viruses, radiation, chemicals, etc
  45. Autosome
    Any chromosome other than sex chromosomes
  46. What number are sex chromosomes?
    Pair #23
  47. Where is the "maleness" gene and what does it do?
    It's on the Y chromosome, there is a Sex-determining Region of the Y chromosome (SRY). When the gene turns on, male characteristics are produced. If it doesn't turn on (even if present) the fetus will be female. For the first 40 days, males and females are exactly alike.
  48. Sex linked inheritance
    Traits on sex chromosomes other than sex: Blood clotting, male pattern baldness, color vision. All on the X chromosome. Aka sex linked genes. Aka X linked genes. The stuff tends to skip generations
  49. Universal donor
    Type O negative
  50. Universal recipient