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 has white flowers?

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?

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

In a population of 5000 in Hardy–Weinberg equilibrium, 1 in 400 show a recessive trait. How many individuals N are expected to be homozygous dominant?

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 for round 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