Heredity:

1. Heredity: The passing of characteristics from parents to offspring

2. Genetics: The science of heredity and the process by which traits are passed from parents to offspring

3. P generation: The 1st two individuals that are crossed (parental generation) F1 generation : The offspring of the P generation (offspring of the parents) F2 generation: The offspring of the F1 generation (offspring of the F1 generation)

5. Mendel’s Hypotheses 1.) For each inherited character ( red, freckles, etc.), an individual has 2 copies of the gene – 1 from each parent

6. Brown Hair Blonde Hair Red Hair Black Hair 2.) There are alternative versions of the gene known as alleles

7. Mother: Brown Hair Father: Blonde Hair Child: Brown Hair 2.) Two different alleles occur together, one of them may be completely expressed while the other shows no observable appearance

8. The expressed form a characteristic as: Dominant R = dominant allele For example R = red hair Rr or RR

9. Trait NOT expressed while the dominant form is present is known as the: recessive allele r = recessive trait = brown hair Rr If the allele combination is rris the recessive trait expressed? _____________ Why or why not?

10. Homozygous - IF 2 alleles of a certain gene are the same, the individual is said to be: homozygous (** true regardless of if the two are dominant OR recessive**)

11. Heterozygous • If the alleles of a gene in an individual are different, the individual is: heterozygous

12. Genotype: set of alleles an individual has for a characteristic Example: Rr is the genotype for red hair

13. Phenotype: the physical appearance of a characteristic So … if the genotype is Rr then the phenotype is ____________________.

14. Questions: T = tan colored feathers t = white color feathers Is t the dominant allele or the recessive allele? _________________ An owl has white colored feathers ( tt ) , this physical appearance of having white feathers is known as the owl’s ________________ ? If an owl’s genotype is Tt, what color feathers will it have? ____________

15. Law of Segregation - states that the two alleles for a characteristic are segregate or SEPARATE when gametes are formed

16. Law of Independent Assortment: --Alleles of different genes separate independently of one another during gamete formation -- The inheritance of one characteristic did not influence the inheritance of any other characteristic

17. Law of Independent Assortment/Segregation Lab B – brown hair b – blonde hair F – freckles f– no freckles C – curly hair c – straight hair G – gap in between front teeth g – no gap in between front teeth

18. Punnett Square: --predicts the outcome of a genetic cross -- the basic 4 chambered Punnett Square can predict the outcome of a monohybrid cross

20. How could you find the genotype of an individual if it was not known? • Test Cross • Is performed when an individual shows a dominant phenotype but we are not sure whether they are heterozygous or homozygous. • These individuals are crossed with a homozygous recessive individual

23. If half of the offspring express the dominant trait and half express the recessive trait, then the unknown individual’s genotype is? ______________________________________

24. IF all of the offspring express the dominant phenotype which genotype is the unknown individual? _____________________________________

26. Section 4: Complex Patterns and Heredity Polygenic Inheritance: when several genes influence a character

27. Incomplete dominance: an individual that displays a phenotype that is intermediate between the two parents

28. Codominance: • red x white ---> red & white spotted

29. Roan Fur in Cattle WW = all white hairs RR = all red hairs RW = red & white hairs together

32. Sex-linked gene’s allele is located ONLY on the X or Y chromosome Carried on the X chromosome and are recessive Males: only have one X chromosome (XY) Male who carries a recessive allele on the X chromosome will express the sex-linked condition

33. Female: if she is a carrier of the recessive allele on one X chromosome, she will NOT exhibit the allele if her other X chromosome exhibits the dominant allele

35. Dihybrid Crosses - A genetic cross that consists of two different traits instead of one

36. Dihybrid Crosses Instead of Rr x rr R= round, r = wrinkled You are now including another traitinto the cross: Y= yellow, y = green RRYY x rryy

37. 1.) Number all of the letters in the crossRRYY X rrYY1 2 3 4 1 2 3 41 and 2 can never be paired together3 and 4 can never be paired togetherYou would pair 1 with 3 and 4You would then pair 2 with 3 and 4 ( these pairings would occur for both genotypesRY, RY, RY, RYrY, rY, rY, rY( these two letter pairings are now the possible gametes from the female and the male)

38. RRYY x rryy Parent 2 Parent 1

39. Parent 2 Parent 1

40. Parent 2 Parent 1

42. Pedigree --- A family history that shows how a trait is inherited over several generations

44. Determining Information From a Pedigree 1.) Autosomal or sex-linked? Autosomal: the gene will appear in both sexes equally - Autosomes are all the other chromosomes other than the X or Y sex chromosome

46. Determining Information From a Pedigree 2. ) Dominant or Recessive Autosomal Dominant: EVERY individual with the condition will have a parent with that condition

47. If the condition is recessive: -- an individual that expresses the condition can have one, two or neither parent express the condition

49. Determining Information From a Pedigree 3.) Homozygous or Heterozygous - if individuals with autosomal traits are homozygous dominant or heterozygous, - their phenotype will show the dominant allele

50. Individual is homozygous recessive, their phenotype will show the recessive allele