What is a testcross?
A)Any genetics cross you do in order to test a hypothesis.
B)Any genetics cross you see on an exam
C)A cross between two organisms of different species
D)A cross between an organism of unknown genotype with a homozygous recessive individual
E)A cross between two true-breeding individual (such as we see in the P generation)

Question

Quizplus · Accepted Answer

A testcross is a cross between an organism of unknown genotype with a homozygous recessive individual, in order to determine the genotype of the unknown organism. This is done by observing the phenotypic ratios of the offspring, which will reveal whether the unknown organism is homozygous dominant or heterozygous for a particular trait. It is an important tool in genetics for determining the genes responsible for certain traits or diseases.

What Is a Testcross