Genetics worksheet with answers

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

1. 1a × a
2. 2a × A
3. 3A × a
4. 4A × A

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

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

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 unaffected son.

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

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?

In a population of 500 in Hardy–Weinberg equilibrium, 1 in 10000 show a recessive trait. How many individuals N are expected to be homozygous dominant?

Two AaBb parents are crossed. Gene A gives round seeds (dominant) or wrinkled seeds; gene B gives black fur (dominant) or white fur. Click the one cell for an offspring that is homozygous for round seeds and for black 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