Question

what is back cross ?

Answer 1

Backcrossing is a crossing of a hybrid with one of its parents or an individual genetically similar to its parent, in order to achieve offspring with a genetic identity which is closer to that of the parent. It is used in horticulture, animal breeding and in production of gene knockout organisms. Backcrossed hybrids are sometimes described with acronym "BC", for example, an F1 crossed with one of its parents (or a genetically similar individual) can be termed a BC1 hybrid, and a further cross of the BC1 hybrid to the same parent (or a genetically similar individual) produces a BC2 hybrid. Back cross is the cross that involves the mating of the F1 hybrid with one of its parent. It can be explained with this example. Suppose a homozygous tall plant having genotype TT is crossed with the homozygous small plant having genotype tt, then their hybrid will be Tt (F1 plant). Now back cross is crossing this Tt individual with either TT or tt individual Outcross is a cross in which two genetically dissimilar members of a species are crossed. It is used to increase genetic variation and is used extensively in animal husbandry. Back-crossing is a crossing of a hybrid individual with one of its parents or an individual genetically similar to its parent, in order to achieve offspring with a genetic identity which is closer to that of the parent. It is used in horticulture, animal breeding. The back-cross in which hybrid individual is crossed with the recessive parent is termed as 'Test Cross'. Test cross is used to identify the genotype of a hybrid individual.