Genetics worksheet with answers

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 has purple flowers?

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)?

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 son.

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

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

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

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