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 is heterozygous (Aa)?

Aa × Aa
P =
2.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 is heterozygous (Aa)?

Aa × aa
P =
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
AA?AaAaaap (A)q (a)p (A)q (a)q² = 0.01N = 2000

In a population of 2000 in Hardy–Weinberg equilibrium, 1% show a recessive trait. How many individuals N are expected to be homozygous dominant?

N = 2000q² = 0.01
N =
6.Hard
AA?AaAaaap (A)q (a)p (A)q (a)q² = 0.0001N = 1000

In a population of 1000 in Hardy–Weinberg equilibrium, 1 in 10000 show a recessive trait. How many individuals N are expected to be homozygous dominant?

N = 1000q² = 0.0001
N =

Answer key

  1. 1. P = 0.5
  2. 2. P = 0.5
  3. 3. P = 0.125
  4. 4. P = 0.25
  5. 5. N = 1620
  6. 6. N = 980.1

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