AP BIOLOGY

Detailed explanation-1: -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-2: -Answer and Explanation: The test performed is a test cross. The test cross determines if the plant is homozygous or heterozygous. In a test cross, the plant under examination is crossed with a homozygous recessive plant for that trait, and the phenotypic ratio of the first generation offspring is observed.

Detailed explanation-3: -An organism can be homozygous dominant, if it carries two copies of the same dominant allele, or homozygous recessive, if it carries two copies of the same recessive allele. Heterozygous means that an organism has two different alleles of a gene.