Genetics worksheet with answers

Free printable Genetics worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

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1.Easy
Aa ♀Aa ♂AaAa????

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?

Aa × Aa
P =
2.Easy
♂ Bb♀ BbbBbB

Two Bb parents are crossed. B gives tall plants and is dominant over b, which gives short plants. Click the cell for an offspring that has tall plants and is homozygous.

Bb × Bb
  1. 1b × b
  2. 2b × B
  3. 3B × b
  4. 4B × B
3.Medium
AaBb ♀AaBb ♂ABAbaBabABAbaBab????????????????

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, round seeds?

AaBb × AaBb
P =
4.Medium
AaBb ♀aaBb ♂ABAbaBabaBabaBab????????????????

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?

AaBb × aaBb
P =
5.Hard
♂ AaBb♀ AaBbAbaBABabAbabaBAB

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

AaBb × AaBb
  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
6.Hard
♂ AaBb♀ AaBbaBAbABababABaBAb

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.

AaBb × AaBb
  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

Answer key

  1. 1. P = 0.25
  2. 2. B × B
  3. 3. P = 0.1875
  4. 4. P = 0.125
  5. 5. AB × AB
  6. 6. Ab × Ab

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