Question

What will the F1 generation produce if pure breeding parents for one trait were crossed as follows: yellow seed, dominant X green seed, recessive?

		100% yellow seeds.
		75% green seeds; 25% yellow seeds.
		50% yellow seeds; 50% green seeds.
		not enough information given.
		75% yellow seeds; 25% green seeds.

Answer 1

Answer : 100 % yellow seeds

It is given that yellow seed is the dominant trait (Y) and green seed is the recessive trait (g).

The cross is between Yellow seed x Green seed

Also, it is given that both parents are purebreeding (i.e, homozygous)

So, homozygous Yellow seed (YY) x homozygous green seed (gg)

The F1 generation refers to the first generation obtained when parents are crossed.

To find the F1 progeny, let us create the Punnet square :

x	g	g
Y	Yg	Yg
Y	Yg	Yg

All the F1 offsprings produced are : Yg

We know that Y is the dominant trait ( Yellow seed ) , which will be expressed.

So, 100 % of the F1 progeny will produce Yellow seeds.