Question

Complete the Punnett square. Heterozygous yellow peas are crossed to homozygous green peas. What are the colors of each possible genotype that would occur in the F1 ? What ratio of genotype and phenotype would be expected in this cross?

Answer 1

To complete a Punnett square for a cross between heterozygous yellow peas and homozygous green peas, list all possible allele combinations. The genotypes in the F1 generation are YY and Yy, with a yellow phenotype. The genotype ratio is 1:1 and the phenotype ratio is 2:0 (yellow:green).

Step-by-step explanation:

To complete the Punnett square for the cross between heterozygous yellow peas (Yy) and homozygous green peas (yy), we need to list all possible combinations of alleles. The heterozygous yellow peas have one dominant allele (Y) and one recessive allele (y), while the homozygous green peas have two recessive alleles (yy). The Punnett square will show the genotypes of the possible offspring.

The Punnett square for this cross would look like this:

YyYYYYyyYyyy

The genotypes that would occur in the F1 generation are YY and Yy, which both result in a yellow phenotype. There are no green genotypes (yy) in this generation. Therefore, all offspring in the F1 generation will have a yellow phenotype.

The ratio of genotypes in the F1 generation is 1:1 (YY:Yy), meaning that there is an equal chance of obtaining either genotype. The ratio of phenotypes in the F1 generation is 2:0 (yellow:green), indicating that all offspring will have a yellow phenotype.