What is the cross between the progeny of `F_1` and homozygous recessive parent called? How is it useful?

A progeny of F_1 , is crossed with the homozygous recessive parent, What is this cross called? Work out how is it useful?

What is the relation between frequency (f) and time period (T) ?

What do the progeny get from parents?

What is the relationship between e.m.f. and magnetic flux?

Two genes 'A' and 'B' are linked. In a dihybrid cross involving these two genes, the F_1 heterozygote is crossed with homozygous recessive parental type (aa bb). What would be the ratio of offspring in the next generation?

cross between unrelated group of organisms is called:

What are bioreactors ? How are they useful ?

What is interaction between two species called?