Question

Differentiate between back cross and test cross.

Answer 1

Aspect	Back Cross	Test Cross
Definition	When an F1 individual is crossed with one of the two parents from which it was derived.	A type of back cross where an F1 individual is crossed with a recessive parent specifically.
Purpose	To produce offspring with dominant traits like the parent used in the cross.	To test whether an individual showing a dominant phenotype is homozygous or heterozygous.
Cross Description	F1 hybrid × one of its original parents (dominant or recessive).	F1 hybrid (unknown genotype) × homozygous recessive parent.
Phenotypic Outcome	Offspring typically show traits of the parent used in back cross.	Both dominant and recessive phenotypes can appear in progeny, revealing genotype of F1.
Example Outcome	Crossing F1 with dominant parent yields all dominant phenotype offspring.	Crossing F1 with recessive parent yields 50% dominant and 50% recessive if heterozygous.
Usage	Used generally to study inheritance patterns.	Used specifically to determine genotype of an individual with dominant phenotype.