1. Genetics Review Problems
Punnett Squares
Pink are general question slides,
Green are simple Punnett Square examples,
Blue are incomplete dominance examples.
Only Pink or Green Questions will be on the Quiz.

2. Use the information in the chart to write the phenotype for each of the following genotypes.
2. yy _____________
3. Ss _____________
4. RR _____________
5. Rr ______________
6. ll _______________

3. Use the information in the chart to write the genotype for each of the following phenotypes.
1. Heterozygous round eyes_________
2. Purebred square ___________
3. Homozygous stubby nose ______
4. Heterozygous yellow ________
5. Blue Color ____________
6. Long nose ____________

4. Cross a heterozygous purple pea plant with a white pea plant.
____ x _____
Trait: T- t-
Phenotypes: Genotypes:

5. George and Gina Guinea Pig are expecting offspring very soon
George and Gina Guinea Pig are expecting offspring very soon. George, a black guinea pig, has two of the same alleles for fur color. Gina has the recessive trait of white fur. What are the chances that their children will look like Gina?
____ x _____
Trait: B- b-
Phenotypes: Genotypes:

6. In rabbits the allele for black coat color (B) is dominant over the allele for brown coat color (b). What is the genotypic ratio and phenotypic ratio for a cross between an animal homozygous for black coat color and one homozygous for brown coat color?
____ x _____
Trait: B- b-
Phenotypes: Genotypes:

7. White hair in sheep is caused by the dominant allele, while black hair is recessive. Cross a heterozygous white male sheep with a black sheep. What are the chances that they will have a black lamb?
____ x _____
Trait: B- b-
Phenotypes: Genotypes:

8. Albinism is recessive in humans
Albinism is recessive in humans. An albino man marries a woman who is not albino, but has an albino father. What are chances of having an albino child?
____ x _____
Trait: B- b-
Phenotypes: Genotypes:

9. In garden peas, round seed coats R is dominant over wrinkled seed coats r. What will the results be of a cross between a homozygous dominant male and a recessive female?
Trait: R- r-
Possible Phenotypes
Possible Genotypes

10. In humans, straight toes T are dominant over curled toes t
In humans, straight toes T are dominant over curled toes t. What would be the result of a cross between a recessive male and a heterozygous female?
Trait: T- t-
Possible Phenotypes
Possible Genotypes

11. Everyone in Squidward’s family has light blue skin, which is the dominant trait. He recently married a gal who has light green skin, which is a recessive trait. Does his family need to worry about the “purebred” family line continuing? Will they have a blue child?
____ x _____
Trait: B- b-
Phenotypes: Genotypes:

12. Mr. Krabbs and his wife recently had a Lil’ Krabby, but it has not been a happy occasion. Mrs. Krabbs is upset that her new baby has shorteyes. Both she and Mr. Krabbs have tall eyeballs the dominant trait. Is is possible that this baby is not hers?
____ x _____
Trait: E- e-
Phenotypes: Genotypes:

13. Phenotypes: Genotypes:
Yellow coat color in guinea pigs is produced by the homozygous genotype (FF). White is produced by the homozygous genotype (F’F’). An intermediate color, cream, is produced by the heterozygous genotype (FF’). What offspring would be expected if two cream colored guinea pigs mated?
____ x _____
Trait: F-
F’-
Phenotypes: Genotypes:

14. Phenotypes: Genotypes:
Hair texture in humans is inherited through incomplete dominance. Curly hair plus straight hair gives you wavy hair. If a man with curly hair marries a woman with straight hair what are the chances that they will have a curly haired child?
____ x _____
Trait: H-
H’-
Phenotypes: Genotypes:

15. Phenotypes: Genotypes:
In an alien species, eye colors can be black, white, or the intermediate gray. What color of eyes will the children of a white eyed mother and a grey eyed father have?
____ x _____
Trait: E-
E’-
Phenotypes: Genotypes:

16. Phenotypes: Genotypes:
In an alien species, eye colors can be black, white, or the intermediate gray. A gray eyed alien and her black eyed husband want a white eyed baby. Is this possible?
____ x _____
Trait: E-
E’-
Phenotypes: Genotypes: