Question

Which is not true for test cross?

• A. F₂ dihybrid test cross ratio $1:1:1:1$ .
• B. It is performed to know the alleles of a gene in an individual.
• C. A test cross is a type of back cross.
• D. Dominant offsprings in test cross is always homozygous.

Answer 1

Answer: (D)

In a test cross, to know the genotype of the individual, it is crossed with a recessive parent. If a plant with dominant phenotype is homozygous than all individual produced shows dominant phenotype. If a plant with dominant phenotype is heterozygous than F₂ dihybrid test cross ratio $1:1:1:1$ .