Multiple choice

Which of the following is a test cross?

  1. Tt x Tt

  2. Tt x tt

  3. Tt x TT

  4. TT x tt

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A test cross involves crossing an individual of unknown genotype (or a known heterozygote) with a homozygous recessive individual to determine the genotype of the unknown parent.