Question 3 – Genetics and evolution - Questions

The fruit color in summer squash (Cucurbita pepo) is determined by two genes, $W / w$ and $Y / y$ .

$W$ is a dominant allele that inhibits pigment deposition, resulting in white fruit.
The recessive allele, $w$ , allows pigment deposition so the fruit develops color.
$Y$ is a dominant allele that codes for the production of a yellow pigment.
Summer squash plants that are homozygous for the recessive allele, $y$ , produce green fruit (in the absence of dominant inhibiting alleles).

A white squash plant was cross-pollinated with a yellow squash plant. All offspring had the genotype $W w Y y$ .

Identify the following:

State the type of gene interaction shown by the genes $W / w$ and $Y / y$ .

Suggest how the dominant allele $W$ inhibits the expression of allele $Y$ .

The fruit color in summer squash (Cucurbita pepo) is determined by two genes, $W / w$ and $Y / y$ .

$W$ is a dominant allele that inhibits pigment deposition, resulting in white fruit.
The recessive allele, $w$ , allows pigment deposition so the fruit develops color.
$Y$ is a dominant allele that codes for the production of a yellow pigment.
Summer squash plants that are homozygous for the recessive allele, $y$ , produce green fruit (in the absence of dominant inhibiting alleles).

A white squash plant was cross-pollinated with a yellow squash plant. All offspring had the genotype $W w Y y$ .

Identify the following:

State the type of gene interaction shown by the genes $W / w$ and $Y / y$ .

Suggest how the dominant allele $W$ inhibits the expression of allele $Y$ .

Genetics and evolution