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 is heterozygous (Aa)?

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)?

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?

red-green colour blindness is X-linked recessive (allele b). A carrier mother, X^BX^b, has children with an affected father, X^bY. The mother's gametes run down the side. Click the cell for an unaffected son.

1. 1X^B × Y
2. 2X^B × X^b
3. 3X^b × Y
4. 4X^b × X^b

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

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 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