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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Name: ____________________   Date: ____________

1.Easy
♂ Bb♀ BbbBbB

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.

Bb × Bb
  1. 1b × b
  2. 2b × B
  3. 3B × b
  4. 4B × B
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 tall, 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, round seeds?

AaBb × Aabb
P =
5.Hard
AAAa?Aa?aap (A)q (a)p (A)q (a)q² = 0.16f = ?

A recessive condition affects 16% of a population in Hardy–Weinberg equilibrium. What fraction f of the population are carriers (heterozygous)?

q² = 0.16
f =
6.Hard
AA?AaAaaap (A)q (a)p (A)q (a)q² = 0.0004N = 500

In a population of 500 in Hardy–Weinberg equilibrium, 1 in 2500 show a recessive trait. How many individuals N are expected to be homozygous dominant?

N = 500q² = 0.0004
N =

Answer key

  1. 1. b × b
  2. 2. P = 0.5
  3. 3. P = 0.375
  4. 4. P = 0.125
  5. 5. f = 0.48
  6. 6. N = 480.2

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