Question

A heterozygous tall yellow plant is crossed with a homozygous short green. Show the genotypes and phenotypes of the F1 offspring and the probability of each?

Answer 1

The F1 offspring from the cross of a heterozygous tall, yellow pea plant (TtYy) and a homozygous short, green pea plant (ttyy) will have a genotypic ratio of 1:1:1:1 and a phenotypic ratio of 50% tall green and 50% short green plants.

Step-by-step explanation:

The question requires understanding of Mendelian genetics and specifically, the outcome of a Punnett square cross between two pea plants with different genotypes.

Let's denote tall as T (dominant) and short as t (recessive), and yellow as Y (dominant) and green as y (recessive). A heterozygous tall, yellow plant is TtYy and a homozygous short, green plant is ttyy.

1. TTyy - Tall plant with green seeds.
2. Ttyy - Tall plant with green seeds.
3. ttyy - Short plant with green seeds.
4. ttyy - Short plant with green seeds.

The genotypic ratio of the F1 offspring is 1:1:1:1, and the phenotypes are: 50% tall green and 50% short green since all yy plants will have green seeds regardless of the height.