LIFE SCIENCE

Detailed explanation-1: -A dog breeder has a stud dog expressing the dominant phenotype. He wants to know the dog’s genotype. How can the breeder determine that information? Mate it with a homozygous recessive female.

Detailed explanation-2: -An organism with one dominant allele and one recessive allele is said to have a heterozygous genotype. In our example, this genotype is written Bb. Finally, the genotype of an organism with two recessive alleles is called homozygous recessive.

Detailed explanation-3: -To identify whether an organism exhibiting a dominant trait is homozygous or heterozygous for a specific allele, a scientist can perform a test cross. The organism in question is crossed with an organism that is homozygous for the recessive trait, and the offspring of the test cross are examined.

Detailed explanation-4: -A test cross is a breeding experiment in which an organism with an unknown genotype associated with the dominant phenotype is mated to an organism that is homozygous for the recessive phenotype.