Genetics worksheet with answers

Two Rr parents are crossed. R gives yellow seeds and is dominant over r, which gives green seeds. Click the cell of the Punnett square for an offspring with green seeds.

1. 1r × R
2. 2r × r
3. 3R × R
4. 4R × r

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?

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

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

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 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 1000 in Hardy–Weinberg equilibrium, 1 in 10000 show a recessive trait. How many individuals N are expected to be homozygous dominant?