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 tall, round 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 unaffected son.

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 black fur (dominant) or white fur; gene B gives yellow seeds (dominant) or green seeds. Click the one cell for an offspring that is homozygous for black fur 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

A recessive condition affects 16% of a population in Hardy–Weinberg equilibrium. What fraction f of the population are carriers (heterozygous)?