Genetics worksheet with answers

Two Rr parents are crossed. R gives tall plants and is dominant over r, which gives short plants. Click the cell for an offspring that has tall plants and is homozygous.

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

Two AaBb parents are crossed. Gene A gives yellow seeds (dominant) or green seeds; gene B gives purple flowers (dominant) or white flowers. Click the one cell for an offspring that is shows both green seeds and white flowers.

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

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