Genetics worksheet with answers

Two Tt parents are crossed. T gives round seeds and is dominant over t, which gives wrinkled seeds. Click the cell of the Punnett square for an offspring with wrinkled seeds.

1. 1t × T
2. 2t × t
3. 3T × T
4. 4T × t

Two Tt parents are crossed. T gives purple flowers and is dominant over t, which gives white flowers. Click the cell of the Punnett square for an offspring with white flowers.

1. 1t × t
2. 2t × T
3. 3T × t
4. 4T × T

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?

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

A recessive condition affects 4% 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 tall plants (dominant) or short plants. Click the one cell for an offspring that is shows white flowers 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