A tall pea plant (T = tall; t = short) displaying the dominant phenotype is bred with a homozygous recessive individual. Half of the offspring produced are tall while the other half are short. What is the probable genotype of the tall parent?

The probable genotype of the tall parent would be Tt.

Explanation:

A tall tea plant can be homozygous dominant (TT) or heterozygous dominant (Tt). If a tall parent is bred with a homozygous recessive individual and produced half tall offspring and half short offspring than the tall parent must be heterozygous dominant for the height trait so the genotype of the male parent would be Tt.

T t

t Tt tt

t Tt tt

If a homozygous dominant individual for tall trait is crossed with the homozygous recessive individual then all tall offspring will be produced because all offspring will have at least one allele for tall trait in them.