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 Bb parents are crossed. B gives round seeds and is dominant over b, which gives wrinkled seeds. Click the cell for an offspring that has round seeds and is homozygous.

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

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

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?

In a population of 5000 in Hardy–Weinberg equilibrium, 16% show a recessive trait. How many individuals N are expected to be homozygous dominant?

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 homozygous for black fur and shows 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