Question

When Mendel crossed a plant homozygous for round seeds to another plant homozygous for wrinkled seeds, he found that all the progeny had round seeds. How is this explained?
a. The allele for round seeds is dominant to the allele for wrinkled seeds.
b. The progeny were homozygous for the allele for round seeds.
c. The parent that was homozygous for round seeds underwent self-pollination.
d. Segregation of alleles in the two parents produced gametes with both alleles.
e. The allele for round seeds is recessive to the allele for wrinkled seeds.

Answer 1

Answer:

a. The allele for round seeds is dominant to the allele for wrinkled seeds.

Explanation:

Mendel found that when two pure breeding plants that differ from each other with respect to one genetic trait are crossed, all the progeny express the phenotype of one parent. The phenotype of the other parent is not expressed in the progeny. He concluded that the genetic trait that is expressed in the F1 generation is dominant over the other which is masked in this generation.

A cross between pure breeding plants for round seeds and the wrinkled seeds obtained all the round seeded progeny. This meant that the phenotype "round" was dominant over the phenotype "wrinkled". If the allele "R" gave round phenotype and the allele "r" imparted wrinkled phenotype, the allele "R" was dominant to the "r".