Mendel crossed peas having round seeds and yellow cotyledons

Mendel crossed peas having round seeds and yellow cotyledons (seed leaves) with peas having wrinkled seeds and green cotyledons. All the F1 plants had round seeds with yellow cotyledons. Based on this cross, what is the probability that an organism in the F2 generation will have round seeds and green cotyledons and be true breeding?

1/16

1/8

1/4

1/32

3/16

3/4

Solution

Round yellow represented as RRYY

Wrinkled green represented as rryy

RRYY * rryy

F1: RrYy All round and yellow

F2 will be as follows:

Round and green = 3/16

Out of the three round & yellow seeds ,two are heterozygous for the dominant R trait (Rr) and will therefore will not breed true.

Therefore only one of the three will breed true i.e RRyy.

So,the probability that an organism in the F2 generation will have round seeds and green cotyledons and be true breeding will be 1/16.

Correct answer is: a.1/16