Genetics worksheet with answers

Two Aa parents are crossed. A gives tall plants and is dominant over a, which gives short plants. Click the cell of the Punnett square for an offspring with short plants.

1. 1a × A
2. 2a × a
3. 3A × A
4. 4A × a

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

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

haemophilia is X-linked recessive (allele h). A carrier mother, X^HX^h, has children with an affected father, X^hY. The mother's gametes run down the side. Click the cell for an affected daughter.

1. 1X^h × X^h
2. 2X^h × Y
3. 3X^H × X^h
4. 4X^H × 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, round seeds?

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

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 black fur (dominant) or white fur. Click the one cell for an offspring that is homozygous for round seeds and for black fur.

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