In pea plants the allele for round seeds (R) are dominant to the allele for wrinkled seeds (r). The allele for yellow seeds (Y) is dominant to the allele for green seeds (y). A heterozygous yellow, round seed plant is crossed with a seed that is green and wrinkled. RrYy x rryy

What are the gamete combinations for the heterozygous parent?
A. RY, rY, Ry, ry
B. rr, yy, YY
C. Ry, ry, yy

The correct answer is -  A. RY, rY, Ry, ry

Explanation:

Gametes are the sex cells or reproductive cells that are haploid in number. Gametes carry only one allele of each gene or chromosome in any organism. The male gamete called an egg or ovum whereas the male gamete called sperm or pollen.

In this case, the heterozygous plant has the genotype RrYy. In each of the gametes, there would one allele of each gene. The gametes get a dominant R and a dominant Y allele and a recessive r and a recessive y allele. Each produces 25% each of RY, Ry, rY, and ry.