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)?

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 a carrier daughter.

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

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 shows white 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

In a population of 2000 in Hardy–Weinberg equilibrium, 16% show a recessive trait. How many individuals N are expected to be homozygous dominant?