1. Complete Dominance Pattern of Inheritance and Punnett Squares

2. Pattern of Inheritance
a description of how contrasting genes on homologous chromosomes interact with one another
when two alleles are different, how do they affect the phenotype

3. Complete Dominance Pattern
when different genes are present in one organism (a heterozygous individual), only one gene is visible in the organism’s phenotype
the dominant gene is visible while the recessive gene is “hidden”

4. Punnett Square
a diagram that predicts the outcome of a genetic cross by considering all possible combinations of gametes in the cross

5. Punnett Square

6. Studying Heredity
Holt Biology, pg. 170

7. Monohybrid Cross
examining the offspring genotype and phenotype possibilities for one gene

8. Punnett Squares and the Law of Segregation
Punnett Squares show two alleles from one parent splitting up
demonstrates Mendel’s Law of Segregation
homologous chromosomes that carry the same genes split during Meiosis 1
allows offspring created to have one allele for each gene from each parent

9. Studying Heredity
Holt Biology, pg. 170

10. Punnett Square

11. Mendel’s Pea Plants’ Flowers Parent Generation Cross
Identification of Alleles P = purple p = white Parent Genotype Identification Purple parent: PP White parent: pp

12. Parent Generation Cross Punnett Square

13. Parent Generation Cross Punnett Square

14. Parent Generation Cross Punnett Square

15. Parent Generation Cross Punnett SquarePp p p

16. Parent Generation Cross Punnett SquarePp p p

17. Parent Generation Cross Punnett SquarePp p p

18. Parent Generation Cross Punnett SquarePp p p

19. Parent Generation Cross
Offspring Genotypic Ratio 4/4 or all or 100 % Pp Offspring Phenotypic Ratio 4/4 or all or 100 % purple

20. Studying Heredity
Holt Biology, pg. 164

21. Mendel’s Pea Plants’ Flowers F1 Generation Cross
Identification of Alleles P = purple p = white Parent Genotype Identification F1 Generation Purple Plant 1: Pp F1 Generation Purple Plant 2: Pp

22. F1 Generation Cross Punnett Square

23. F1 Generation Cross Punnett Square

24. F1 Generation Cross Punnett Square

25. F1 Generation Cross Punnett SquarePP P p

26. F1 Generation Cross Punnett SquarePP Pp P p

27. F1 Generation Cross Punnett SquarePP Pp P p

28. F1 Generation Cross Punnett SquarePP Pp pp P p

29. F1 Generation Cross
Offspring Genotypic Ratio 1 PP : 2 Pp : 1 pp Offspring Phenotypic Ratio 3 purple : 1 white

30. What would the offspring represented in these boxes be called
What would the offspring represented in these boxes be called? Punnett Square P p PP Pp pp P p
F2 Generation

31. In garden peas, long stems (L) are dominant and short stems (l) are recessive. If a homozygous long plant is crossed with a homozygous short plant, what will the genotypic and phenotypic ratios be?
Identification of Alleles L = long stems l = short stems Parent Genotype Identification LL ll

32. In garden peas, long stems (L) are dominant and short stems (l) are recessive. If a homozygous long plant is crossed with a homozygous short plant, what will the genotypic and phenotypic ratios be?
Punnett Square L L l l

33. In garden peas, long stems (L) are dominant and short stems (l) are recessive. If a homozygous long plant is crossed with a homozygous short plant, what will the genotypic and phenotypic ratios be?
Punnett Square L L Ll l l

34. In garden peas, long stems (L) are dominant and short stems (l) are recessive. If a homozygous long plant is crossed with a homozygous short plant, what will the genotypic and phenotypic ratios be?
Punnett Square L L Ll l l

35. In garden peas, long stems (L) are dominant and short stems (l) are recessive. If a homozygous long plant is crossed with a homozygous short plant, what will the genotypic and phenotypic ratios be?
Punnett Square L L Ll l l

36. In garden peas, long stems (L) are dominant and short stems (l) are recessive. If a homozygous long plant is crossed with a homozygous short plant, what will the genotypic and phenotypic ratios be?
Punnett Square L L Ll l l

37. In garden peas, long stems (L) are dominant and short stems (l) are recessive. If a homozygous long plant is crossed with a homozygous short plant, what will the genotypic and phenotypic ratios be?
Offspring Genotypic Ratio 4/4 or all or 100% Ll Offspring Phenotypic Ratio 4/4 or all or 100% long stems

38. What will the genotypic and phenotypic ratios be if we cross the F1 (offspring) from the previous problem?
Identification of Alleles L = long stems l = short stems Parent Genotype Identification Ll

39. What will the genotypic and phenotypic ratios be if we cross the F1 (offspring) from the previous problem?
Punnett Square L l L l

40. What will the genotypic and phenotypic ratios be if we cross the F1 (offspring) from the previous problem?
Punnett Square L l LL L l

41. What will the genotypic and phenotypic ratios be if we cross the F1 (offspring) from the previous problem?
Punnett Square L l LL Ll L l

42. What will the genotypic and phenotypic ratios be if we cross the F1 (offspring) from the previous problem?
Punnett Square L l LL Ll L l

43. What will the genotypic and phenotypic ratios be if we cross the F1 (offspring) from the previous problem?
Punnett Square L l LL Ll ll L l

44. What will the genotypic and phenotypic ratios be if we cross the F1 (offspring) from the previous problem?
Offspring Genotypic Ratio 1 LL : 2 Ll : 1 ll Offspring Phenotypic Ratio 3 long stems : 1 short stem

45. Identification of Alleles Parent Genotype Identification
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for inflated pea pods with a plant that is homozygous for constricted pea pods. What are the genotypes and phenotypes?
Identification of Alleles Parent Genotype Identification

46. The Work of Gregor Mendel (a little background information…)
Holt Biology, pg. 163

47. Identification of Alleles Parent Genotype Identification
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for inflated pea pods with a plant that is homozygous for constricted pea pods. What are the genotypes and phenotypes?
Identification of Alleles Parent Genotype Identification

48. When no letters are assigned to different alleles, what should you do?
Make them up!
What are “typical” letters to use?
Most often, the first letter of a term that describes the dominant trait is used.

49. In garden peas inflated pods are dominant to constricted pods
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for pea pods with a plant that is homozygous for inflated pea pods. What are the genotypes and phenotypes?
Identification of Alleles I = inflated pea pods i = constricted pea pods Parent Genotype Identification Ii II

50. In garden peas inflated pods are dominant to constricted pods
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for pea pods with a plant that is homozygous for inflated pea pods. What are the genotypes and phenotypes?
Punnett Square I i I I

51. In garden peas inflated pods are dominant to constricted pods
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for pea pods with a plant that is homozygous for inflated pea pods. What are the genotypes and phenotypes?
Punnett Square I i II I I

52. In garden peas inflated pods are dominant to constricted pods
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for pea pods with a plant that is homozygous for inflated pea pods. What are the genotypes and phenotypes?
Punnett Square I i II Ii I I

53. In garden peas inflated pods are dominant to constricted pods
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for pea pods with a plant that is homozygous for inflated pea pods. What are the genotypes and phenotypes?
Punnett Square I i II Ii I I

54. In garden peas inflated pods are dominant to constricted pods
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for pea pods with a plant that is homozygous for inflated pea pods. What are the genotypes and phenotypes?
Punnett Square I i II Ii I I

55. Offspring Genotypic Ratio 2 II : 2 Ii Offspring Phenotypic Ratio
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for pea pods with a plant that is homozygous for inflated pea pods. What are the genotypes and phenotypes?
Offspring Genotypic Ratio 2 II : 2 Ii Offspring Phenotypic Ratio

56. When numbers have a common factor, simplify them in the ratio.

57. Offspring Genotypic Ratio 2 II : 2 Ii Offspring Phenotypic Ratio
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for pea pods with a plant that is homozygous for inflated pea pods. What are the genotypes and phenotypes?
Offspring Genotypic Ratio 2 II : 2 Ii Offspring Phenotypic Ratio

58. In garden peas inflated pods are dominant to constricted pods
In garden peas inflated pods are dominant to constricted pods. Cross a plant that is heterozygous for pea pods with a plant that is homozygous for inflated pea pods. What are the genotypes and phenotypes?
Offspring Genotypic Ratio 2 II : 2 Ii 1 II : 1 Ii Offspring Phenotypic Ratio 4/4 or all or 100% inflated pea pods

59. What will the genotypic and phenotypic ratios be if garden pea plants which have heterozygous inflated pods and constricted pods are crossed?
Identification of Alleles I = inflated pea pods i = constricted pea pods Parent Genotype Identification Ii

60. How will you know the genotype of the constricted pea pod parent?
When a recessive trait is visible in the phenotype, only 1 genotype of possible
Homozygous recessive

61. What will the genotypic and phenotypic ratios be if garden pea plants which have heterozygous inflated pods and constricted pods are crossed?
Identification of Alleles I = inflated pea pods i = constricted pea pods Parent Genotype Identification Ii ii

62. What will the genotypic and phenotypic ratios be if garden pea plants which have heterozygous inflated pods and constricted pods are crossed?
Punnett Square I i i i

63. What will the genotypic and phenotypic ratios be if garden pea plants which have heterozygous inflated pods and constricted pods are crossed?
Punnett Square I i Ii i i

64. What will the genotypic and phenotypic ratios be if garden pea plants which have heterozygous inflated pods and constricted pods are crossed?
Punnett Square I i Ii ii i i

65. What will the genotypic and phenotypic ratios be if garden pea plants which have heterozygous inflated pods and constricted pods are crossed?
Punnett Square I i Ii ii i i

66. What will the genotypic and phenotypic ratios be if garden pea plants which have heterozygous inflated pods and constricted pods are crossed?
Punnett Square I i Ii ii i i

67. What will the genotypic and phenotypic ratios be if garden pea plants which have heterozygous inflated pods and constricted pods are crossed?
Offspring Genotypic Ratio 1 Ii : 1 ii Offspring Phenotypic Ratio 1 inflated pea pod : 1 constricted pea pod