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?

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

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

Two AaBb parents are crossed. Gene A gives purple flowers (dominant) or white flowers; gene B gives black fur (dominant) or white fur. Click the one cell for an offspring that is homozygous for purple flowers 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