Genetics worksheet with answers

Two Aa parents are crossed. A gives round seeds and is dominant over a, which gives wrinkled seeds. Click the cell for an offspring that has round seeds and is homozygous.

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

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

1. 1R × R
2. 2R × r
3. 3r × R
4. 4r × r

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?

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

1. 1X^h × Y
2. 2X^h × X^H
3. 3X^H × Y
4. 4X^H × X^H

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

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 tall plants (dominant) or short plants; gene B gives round seeds (dominant) or wrinkled seeds. Click the one cell for an offspring that is homozygous for tall plants and shows wrinkled 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