Question

To determine whether $F_1$ hybrid is homozygous or heterozygours for a particular trait .......... cross is performed.

• A. Monohybrid
• B. Test
• C. Back
• D. Reciprocal

Answer 1

The correct option is B Test

Test cross is a cross performed between an organism with unknown dominant genotype and an organism homozygous recessive for the trait. It helps in determining whether the individual being tested is homozygous dominant or heterozygous for the trait. If all the individuals produced in F1 generation show phenotypically dominant trait then the tested organism is homozygous dominant and if half show phenotypically dominant trait and half show recessive trait then the organism to be tested is heterozygous.

A monohybrid cross is a cross between two organisms involving one trait only.

Back cross is a cross of the hybrid with either of the pure parents. Thus a back cross can be a test cross but a test cross cannot be a back cross always.

Reciprocal cross involves a pair of crosses taht reverses the sexes associated with each genotype. It is used to test the role of parental sex on a given inheritance pattern.

Thus, the correct answer is option B.