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 has purple flowers?

Duchenne muscular dystrophy is X-linked recessive (allele d). A carrier mother, X^DX^d, has children with an affected father, X^dY. The mother's gametes run down the side. Click the cell for an affected son.

1. 1X^d × X^d
2. 2X^d × Y
3. 3X^D × X^d
4. 4X^D × Y

red-green colour blindness is X-linked recessive (allele b). A carrier mother, X^BX^b, has children with an affected 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

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