If 2 heterozygous pea plants with yellow round seeds are crossed, what is the ratio of the yellow round seed?

If two heterozygous pea plants are crossed with yellow round seeds, the resulting progeny mostly show the dominant phenotype.

Explanation:

Plants with two different alleles of a gene are heterozygous. As all the heterozygous offspring are yellow, then the yellow allele must be dominant over the recessive green allele.

Y y

Y YY Yy

y Yy yy