Genetics worksheet with answers

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

1. 1b × B
2. 2b × b
3. 3B × B
4. 4B × b

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?

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, round seeds?

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

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 both wrinkled seeds 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

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