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)?

Two Aa parents are crossed. A gives yellow seeds and is dominant over a, which gives green seeds. Click the cell for an offspring that has yellow seeds and is homozygous.

1. 1A × a
2. 2A × A
3. 3a × a
4. 4a × A

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, wrinkled seeds?

haemophilia is X-linked recessive (allele h). A carrier mother, X^HX^h, has children with an unaffected father, X^HY. The mother's gametes run down the side. Click the cell for a carrier daughter.

1. 1X^h × Y
2. 2X^h × X^H
3. 3X^H × Y
4. 4X^H × X^H

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

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)?