Chapter 10

  1. Blending Theory of Inheritance-
    organisms contribute equally offspring so that the offspring will have an intermediate appearance
  2. Gregor Mendel-
    1860's, Australian monk, father of
  3. monohybrid Inheritance-
    Cross of organisms that differ in 1 trait
  4. Parental generation-
    (P) tall x short
  5. First filial generation-
    (F1) tall x tall
  6. Second filial generation-
    (F2) tall x short
  7. Mendel's Law of Segregation-
    each organism contains 2 factors for each trait, and the factors segregate during the formation of gametes so that each gamete contains only one factor from each pair of factors. When fertilization occurs, the new organism will have 2 factors for each trait, 1 from each parent.
  8. Alleles-
    alternate forms of a gene
  9. Dominant allele-
    masks the expression of a recessive allele
  10. Recessive Allele-
    expression is hidden by a dominant allele
  11. Gene Locus-
    location on a chromosome where an allele occurs
  12. Homozygous-
    organism has 2 identical alleles for a trait
  13. Heterozygous-
    organism has 2 different alleles for trait
  14. Genotype-
    the alleles an individual receives at fertilization
  15. Phenotype- 
    The physical appearance of an individual
  16. Punnett square-
    a grid-like devicefor working simple genetic crosses
  17. Monohybrid Test Cross-
    Determines whether an individual with the dominant phenotype is homozygotes or heterozygotes
  18. Dihybrid Test Cross-
    • determines if an individual with the dominant phenotype is homozygotes or heterozygotes
    • done by crossing the dominant with recessive
    • if homozygous dominant, all offspring show the same
    • if heterozygous, offspring will have a 1:1:1:1
  19. Tt x Tt
  20. Tt x tt
  21. TtGg x TtGg
  22. TtGg x ttgg
  23. Pedigree Charts-
    • show the pattern of inheritance
    • constructed to predict whether a couple is likely to pass on genetic disorder
  24. Incomplete dominance-
    • off spring show characteristics intermediateof the parents
    • NOT the blending theory of inheritance because parantal phenotypes reappear in the F2 generation
  25. Phenotype- A
    Genotype- AA, AO
  26. B
    BB BO
  27. AB
  28. O
  29. Codominance-
    both alleles of a gene are equally expressed
  30. Polygenic Inheritance-
    • One trait controlled by several pairs of alleles. 
    • Each dominant allele contributes in an equal and additive manner
  31. Human Polygenic traits-
    height, skin color, behavior
  32. Human polygenic disorders-
    cleft lip, cleft palate,club foot, high BP, cancer, diabetes
  33. Pleiotropy-
    • a gene that affects more than one phenotypic trait
    • Ex. Albinism-aa- cannot produce melanin
    • Marfan syndrome-long lany, abnormal collegan
  34. What affects the phonotype?
  35. X-linked recessive inheritance characteristics-
    • More males than females are affected
    • an affected son can have parents who have the normal phenotype.
    • for a female to have the characteristic, her father must also have it. Her mother must have it or be a carrier,
    • the characteristic often skips a generation from the grandfather to the grandson
    • if a woman has the chracteristic, all of her sons will have it
Card Set
Chapter 10
Chapter 10 Mendelion Patterns of Inheritance