In a watermelon, the green color of the fruit dominates over the striped one

In a watermelon, the green color of the fruit dominates over the striped one. Determine the color of the fruits of watermelons from crossing plants with genotypes: a) AA and aa b) Aa and Aa c) Aa and aa

Let’s designate the dominant gene that causes the green color of the watermelon by the letter “A”, then the recessive gene that causes the striped color will be “a”.

and). A homozygous green-fruited variety of watermelons – AA. Sex cells are A-type.

The striped variety of watermelons is aa, because homozygosity is a condition under which a recessive trait acquires the ability to be realized in a phenotype. It will produce a-type germ cells. When such watermelons are crossed, all descendants will be striped carriers of the Aa genotype.

b). When heterozygous green watermelons are crossed with each other, we get offspring with a splitting of the type 1AA: 2Aa: 1aa; by phenotypic characteristics:

striped watermelons (AA, Aa) – 75%;

green watermelons (aa) – 25%.

in). Striped watermelons – aa, produce gametes a.

Green watermelons – Aa, gametes – A and a.

When crossing such watermelons, we get the following offspring options:

green watermelons (Aa);

striped watermelons (aa).

The ratio of green to striped watermelons is 1: 3.