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 white flowers?

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)?

red-green colour blindness is X-linked recessive (allele b). A carrier mother, X^BX^b, has children with an unaffected father, X^BY. The mother's gametes run down the side. Click the cell for an affected son.

1. 1X^B × X^B
2. 2X^B × Y
3. 3X^b × X^B
4. 4X^b × Y

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?

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

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