1. Complex Patterns of Inheritance
Punnett Squares Day 2
Complex Patterns of Inheritance

2. BELL RINGER 5 MIN Have homework out and ready to turn in
Write today’s learning target
Answer this question to the right.   
HINT: Use a punnett square!
Two parents are heterozygous for a given trait. What percentage of the offspring of the two parents will be homozygous for the same trait?

3. T t Tt T t TT Tt tt 25% BELL RINGER 5 MIN Two parents are
heterozygous for a
given trait. What
percentage of the
offspring of the two
parents will be
homozygous for
the same trait?
T t Tt T t TT Tt tt
25%

4. Agenda Bell Ringer (5 Min) Introduction (5 Min)
Notebook Input (20 Min)
Notebook Output (5 Min)
The Ms. Wynn Show (30 Min)
Independent Practice (15 Min)
Exit Ticket (10 Min)

5. What Happened Here?

6. What Happened Here?

7. What Happened Here?

8. What Happened Here?

9. What Happened Here?

10. Notebook Input Today you write everything that is underlined.
The title of your notes is:
Complex Patterns of Inheritance

11. Simple Dominance
One trait is always dominant over the other, so there are only two choices:
Tall OR short
Pink OR white
Round OR oval
BUT, some genes are more complex….

12. Review: Predicting Traits
Punnett squares are charts that show possible gene combinations and the probability of each combination occurring.
November 16, 2018

13. Review: Simple Dominance Example
SpongeBob is known for his big round eyes (R), which are dominant over an oval eye shape (r). If he is heterozygous for his round eye shape and marries a homozygous recessive woman, what are the expected phenotype percentages of his kids?

14. Let’s put this into action!
Step 1: List the genotypes of the parents:
Heterozygous eyes: ____
Homozygous recessive eyes: ____ Rr rr

15. Step 2: Make a Punnett Square
Heterozygous eyes: Rr
Homozygous recessive: rr
R r Rr rr r Rr rr

16. Step 3: Answer the question
What are the expected phenotype percentages of his kids?
50% round (Rr)
50% oval (rr)

17. Complex Genetics Cases

18. Incomplete dominance Phenotype of heterozygote is a blending of trait
Two capital letters are used since neither is dominant over the other

19. Incomplete dominance
Incomplete dominance – offspring show a blending of traits from parent to parent.
Neither allele is completely dominant over the other.
November 16, 2018

20. Incomplete dominance
Example:
CRCR = red
CWCW = white
CRCW = pink

21. Incomplete Dominance
November 16, 2018

22. Incomplete Dominance
A red flower and pink flower are crossed. What are the resulting offspring phenotypes and percentages?
Step 1: List the genotypes of the parents
Red flower: _______
Pink flower: _______
CRCR
CRCW

23. Incomplete Dominance Example
Step 2: Make a Punnett square
CR CR
CRCR CR CW
CRCR
CRCW
CRCW

24. Incomplete Dominance Example
Step 3: Answer the question
What are the resulting offspring phenotypes and percentages?
CR CR
CRCR CR CW
CRCR
50% red
50% pink
CRCW
CRCW

25. Co-dominance x Co- = _________
BOTH alleles are expressed, (no blending) in the heterozygote
Two capital letters are used since neither is dominant over the other
together x

26. Co-dominance
Co-dominance does not involve blending.
November 16, 2018

27. Co-dominance x Example: FBFB = black feathers
FBFW = black AND white feathers
FWFW = white feathers x

28. Co-dominance Example
A black rooster and a black-and-white chicken mate. What are the resulting percentages of each possible phenotype?
Step 1: List the genotypes of the parents
Black rooster: _______
Black-and-white chicken: _______
FBFB
FBFW

29. FB FB FBFB FB FW FBFB FBFW FBFW Co-Dominance Example
Step 2: Make a Punnett square
A black rooster and a black-and-white chicken mate. What are the resulting percentages of each possible phenotype?
FB FB
FBFB FB FW
FBFB
FBFW
FBFW

30. FB FB FBFB FB FW FBFB FBFW FBFW 50% black 50% black-and-white
Co-Dominance Example
Step 3: Answer the question: What are the resulting percentages of each possible phenotype?
FB FB
FBFB FB FW
FBFB
FBFW
FBFW
50% black
50% black-and-white

31. Multiple Alleles
Definition: More than 2 alleles are available for a certain gene
Example: Hair color (blonde, black, brown, red,…)

32. Multiple alleles
Even if more than two alleles exist in a population, any given individual can have no more than two of them: one from the mother and one from the father.
In Labrador retriever, coat color is determined by one gene with four different alleles. Five different colors result from the combinations of these alleles.
November 16, 2018

33. Multiple Allele Example
Example: The gene for color of pigeon wings has three possible alleles: ash red, blue, and brown.

34. Multiple Allele Example
In humans, there are 3 possible alleles for blood type:
Allele
Codes for IA
Type A blood
(make “A” carbohydrates) IB
Type B blood
(make “B” carbohydrates) i
Type O blood
(make neither carbohydrate)

35. Multiple Allele Example
Genotype
Phenotype
IAIA
Type A blood
IAi
IBIB
Type B blood
IBi
IAIB
Type AB blood ii
Type O blood

37. Multiple Allele Example
A mother with blood type A and father with blood type B take home their baby. They later discover that their child has type O blood. Did the hospital make a mistake?
Step 1: List the genotypes of the parents
Mother, blood type A: _________
Father, blood type B: _________
IAIA, IAi
IBIB, IBi

38. Multiple Allele Example
A mother with blood type A and father with blood type B take home their baby. They later discover that their child has type O blood. Did the hospital make a mistake?
IA i
IBi IB i
IAIB
IAi ii

39. Multiple Allele Example
Step 3: Did the hospital make a mistake?
25% chance of type O blood
IA i
IBi IB i
IAIB
IAi ii

40. Incomplete dominance or Codominance??
The phenotype of the heterozygote is intermediate from the parent’s phenotype.
Two checkered (black and white) chicken are crossed. They produce offspring with three phenotypes: black, white, and checkered.
A red-flowered plant is crossed with a white-flowered plant. All of the offspring are pink.
A cross between a purebred animal with red hairs and a purebred animal with white hairs produces and animal that has both red hairs and white hairs.
To The Teacher:
Use the following questions to check for understanding.
A red-flowered plant is crossed with a white-flowered plant. All of the offspring are pink. Incomplete dominance.
A cross between a purebred animal with red hairs and a purebred animal with white hairs produces and animal that has both red hairs and white hairs. Codominance.
The phenotype of the heterozygote is intermediate from the parent’s phenotype. Incomplete dominance.
Two checkered (black and white) chicken are crossed. They produce offspring with three phenotypes: black, white, and checkered. Codominance.

41. Notebook Output 5 MIN
People are historically discriminated based on skin color. How could science educate people to think twice about their prejudices?

42. Who is NOT the father?
The Ms. WYNN show

43. Before the show begins, answer the following question: A mother has type O blood and a father has type AB blood. What are the possible phenotypes of their children?

44. 50% type A blood (all IAi) 50% type B blood (all IBi)

45. Please, work together with your groups
Please, work together with your groups. Based on the information in the following slides, which man/men could be the father of the baby. Justify your answer using a Punnett Square.

46. Case #1

47. The Mother – Type A Blood

48. The Baby – Type B Blood

49. Before we look at the possible fathers, what are the mother and baby’s genotypes?

50. Mother (Type A): IAIA or IAi Baby (Type B): IBIB or IBi

51. Possible Father #1: Sammy the Player. Type O Blood

52. Possible Father #2: Billy the businessman. Type AB Blood

53. Possible Father #3: The Waiter. Type A Blood

54. Possible Father #4: The Cable Guy. Type B Blood

55. Work it out!!!

56. Sammy, you are NOT the father. Waiter, you are NOT the father
Sammy, you are NOT the father! Waiter, you are NOT the father! Neither one of you have any B alleles! Two possible fathers: Billy the Businessman and the Cable Guy

57. Case #2

58. The Mother – Type AB Blood

59. The Baby – Type B Blood

60. Before we look at the possible fathers, what are the mother and baby’s genotypes?

61. Mother: IAIB Baby: IBIB, IBi

62. Possible Father # 1: Greg the teacher Type O Blood

63. Possible Father #2: Anthony the Accountant Type A Blood

64. Possible Father #3 Brad the Barista Type AB Blood

65. Possible Father #4 Jose the Doctor Type B Blood

66. Work it out!!!

67. All of you could be the fathers! All have either a B or O allele!!

68. Case #3

69. The Mother – Type O Blood

70. The Baby – Type AB Blood

71. Before we look at the possible fathers, what are the mother and baby’s genotypes? Mother (Type O): Baby (Type AB):

72. Mother: ii Baby: IAIB

73. Possible Father #1: The Artist. Type O Blood

74. Possible Father #2: Guy at the club. Type AB Blood

75. Possible Father #3: Cabdriver. Type A Blood

76. Possible Father #4: Jared the Flight Attendant. Type B Blood

77. Work it out!!!

78. Mom, you are NOT the right mother
Mom, you are NOT the right mother!! They must have switched your baby at the hospital!

79. Mother: ii Baby: IAIB

80. Independent Practice 15 MIN

81. Exit Ticket – EOC ATTACK!
A species of jungle chicken is codominant
for red and white feathers. What color
would be expressed in the offspring
represented by the missing square below if
T is dominant for red feathers and t is
recessive for white feathers?
Red
Pink
White
Speckled ( a mix of red and white)
November 16, 2018

82. HOME LEARNING
Simpsons Genetic Probability Worksheet