Distinguishing Monohybrid Cross and Testcross
Monohybrid Cross
Monohybrid cross may be defined as the cross done by taking single trait at a time. The ratio of the monohybrid cross by the pure parent breed result in the formation of 3:1 phenotype in the second generation. The genotype ratio is 1:2:1.
Test Cross
Test cross may be defined as the cross between the unknown genotype and the recessive parents. This cross is done to determine whether the genotype is heterozygous or the homozygous dominant trait. The ratio of the cross may vary depending on the genotype of the organism.
Distinguish between a monohybrid cross and a testcross. Monohybrid cross involves crossing two purebred parents, each with different alleles for a single gene, to produce offspring with a genotype ratio of 1:2:1 and a phenotype ratio of 3:1 in the second generation. Testcross, on the other hand, is a cross between an individual with an unknown genotype and a homozygous recessive individual to determine the genotype of the unknown individual. The outcome of a testcross can help determine whether the unknown individual is homozygous dominant or heterozygous for a particular trait.