1. The contrasting traits for hair color in guinea pigs are black (B) and white (b). What are the genotype pairs for hair color?
2. In humans, albinism (a lack of pigment in the skin, eyes, and hair) is due to a homozygous recessive condition.
a. Write the genotype pairs for this condition.
b. Write the possible pairs that normal-colored people have.
3. Which of the following genotypes are heterozygous? AA, Aa, Yy, Rr, RR
4. Green is the dominant color for pods of pea plants. Yellow is recessive. What are the phenotypes of the following allele pairs? GG, Gg, gg
5. In a pea plant that breeds true for tall, what possible gametes can be produced?
6. In a pea plant that breeds true for dwarf, what possible gametes can be produced?
7. Use a punnett square to determine the possible genotypes of the F1 generation when a heterozygous black rabbit is crossed with a homozygous brown rabbit. (Black hair is dominant to brown hair in rabbits.)
8. White hair is dominant over black hair in sheep. A white male and a black female are parents of a black lamb. What is the probability that their next lamb will be white?
9. What will be the phenotype of the F1 generation produced by a cross between a true-breeding tall and a true-breeding dwarf? (tall is dominant)
10. The ability to taste a bitter chemical, phenylthiocarbamide (PTC) is due to a dominant allele. In terms of tasting ability, what are the possible phenotypes of a man who has one parent who is a taster and one who is a non-taster? What are his possible genotypes?
11. If the man from the problem above marries a woman who is a non-taster, what proportion of their children would be tasters?
12. Predict the offspring of a vestigial-winged fruit fly and a homozygous normal-winged fruit fly. (normal wings is dominant). Predict the F1 offspring.
13. The contrasting traits for hair color in guinea pigs are black (B) and white (b). A heterozygous black haired guinea pig is bred with white guinea pig. What are the chances that they will have a white guinea pig?
14. The contrasting traits for air texture in guinea pigs are rough (R) and smooth (r). A homozygous rough-haired guinea pig is bred with a smooth guinea pig. What are the chances that they will have a rough guinea pig?
15. In humans, albinism (a lack of pigment in the skin, eyes, and hair) is due to a homozygous recessive condition. What are the chances that two carriers (heterozygous) of albinism will have normal children?
16. White hair is dominant over black hair in sheep. A white male and a black female are parents of a black lamb. What is the genotype of the father?
17. The ability to taste a bitter chemical, phenylthiocarbamide (PTC) is due to a dominant allele (T). In terms of tasting ability, what are the possible genotypes of a man whose parents are both non-tasters?
18. Predict the offspring of a vestigial-winged fruit fly and a homozygous normal winged fruit fly. (Normal wings is dominant).
19. A family has four daughters. What is the probability that the fifth child would be a female?
20. You have just flipped a coin five times and it has turned up heads every time. What are the chances that the next time you flip it, it will be tails?
21. Purple flower color in bluets (P) is codominant to white flower color (W). Flowers that are heterozygous for this condition are violet. If a violet bluet and a purple bluet breed, what percentage of their offspring will be violet?
22. In four o'clocks, red flower color and white flower color are incompletely dominant. What is the phenotypic ratio for a cross between a red four o'clock and a pink four o'clock?
23. Black (B) and white (W) coat color a co-dominant in cows. Cows that have both genes are spotted. What are the chances that black cow and a spotted cow will have a white calf?
24. What are the chances that a mother who carries the gene for cleft palate and a father who is normal will have a child with a cleft palate? (Cleft palate (c) is due to a sex-linked, recessive trait).
25. If straight hair and curly hair show incomplete dominance, then what are the chances that a straight haired parent and a wavy haired parent will have a curly haired child?
26. Long stems in pea plants is dominant over short stems. Two long-stemmed pea plants cross -pollinate and the resulting seeds produce: 787 long stemmed pea plants, 277 short-stemmed pea plants. What does this information tell you about the genotype of the parents?
27. What are the chances that a color-blind man and a normal-vision woman will have a color blind son?
28. In rabbits, albinism is due to a homozygous recessive condition. What are the chances that two carriers (heterozygous) of albinism will have normal children?