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)?

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

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 tall, round seeds?

In a population of 5000 in Hardy–Weinberg equilibrium, 1 in 1600 show a recessive trait. How many individuals N are expected to be homozygous dominant?

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