AP BIOLOGY

Detailed explanation-1: -Specifically, to detect the underlying genotype of an organism with a dominant phenotype, one must do a type of breeding analysis called a test cross. The test cross is another fundamental tool devised by Gregor Mendel.

Detailed explanation-2: -A dominant allele produces a dominant phenotype in individuals who have one copy of the allele, which can come from just one parent. For a recessive allele to produce a recessive phenotype, the individual must have two copies, one from each parent.

Detailed explanation-3: -In order to find the unknown genotype of the dominant character, a cross breeding is performed which is called test crossing. Here the unknown dominant character is crossed with the known recessive character, for example, tall plant (its genotype is not known) is crossed to dwarf (its genotype is known).

Detailed explanation-4: -A test cross can be used to determine whether an organism with a dominant phenotype is homozygous or heterozygous. In a test cross, a parent with a dominant phenotype but unknown genotype is crossed with a recessive parent.