Genetics worksheet with answers

Two Bb parents are crossed. B gives yellow seeds and is dominant over b, which gives green seeds. Click the cell of the Punnett square for an offspring with green seeds.

1. 1b × b
2. 2b × B
3. 3B × b
4. 4B × B

In pea plants, purple flowers (A) are dominant over white (a). A plant with genotype Aa is crossed with a plant with genotype aa. What is the probability P that an offspring is heterozygous (Aa)?

Duchenne muscular dystrophy is X-linked recessive (allele d). A carrier mother, X^DX^d, has children with an unaffected father, X^DY. The mother's gametes run down the side. Click the cell for an affected son.

1. 1X^d × X^D
2. 2X^d × Y
3. 3X^D × X^D
4. 4X^D × Y

Tall (A) is dominant over short (a), and round seeds (B) over wrinkled (b). The genes are on different chromosomes. For the cross AaBb × Aabb, what is the probability P that an offspring is short, wrinkled seeds?

Two AaBb parents are crossed. Gene A gives purple flowers (dominant) or white flowers; gene B gives yellow seeds (dominant) or green seeds. Click the one cell for an offspring that is homozygous for purple flowers and shows green seeds.

1. 1ab × aB
2. 2ab × ab
3. 3ab × AB
4. 4ab × Ab
5. 5AB × aB
6. 6AB × ab
7. 7AB × AB
8. 8AB × Ab
9. 9Ab × aB
10. 10Ab × ab
11. 11Ab × AB
12. 12Ab × Ab
13. 13aB × aB
14. 14aB × ab
15. 15aB × AB
16. 16aB × Ab

Two AaBb parents are crossed. Gene A gives round seeds (dominant) or wrinkled seeds; gene B gives yellow seeds (dominant) or green seeds. Click the one cell for an offspring that is shows wrinkled seeds and is homozygous for yellow seeds.

1. 1Ab × Ab
2. 2Ab × aB
3. 3Ab × ab
4. 4Ab × AB
5. 5ab × Ab
6. 6ab × aB
7. 7ab × ab
8. 8ab × AB
9. 9aB × Ab
10. 10aB × aB
11. 11aB × ab
12. 12aB × AB
13. 13AB × Ab
14. 14AB × aB
15. 15AB × ab
16. 16AB × AB