This question deals with simple Mendelian inheritance. In particular, this question deals with a
Monohybrid cross.
The first part of the question states that "breed of chicken has been developed with a
PURE trait for silky feathers." This means that chickens that have silky feathers are either going to be
Homozygous Dominant or
Homozygous Recessive. We DON'T know this yet.
From the cross mentioned in the question: Hens (silky feathers) x Roosters (normal feathers) = All offspring are normal. This tells you that the
dominant trait are the normal feathers and the
recessive trait are the silky feathers.
So, let's define our alleles:
Let the A allele be dominant.
Let the a allele be recessive.
So, this will be your cross:
silky feathers (aa) x normal feathers (AA). Note: the normal feathers CANNOT be heterezygous or otherwise that will give you 1/2 silky and 1/2 normal. The question says ALL offspring are normal.
So, when you do your monohybrid cross, you get 3/4 Normal and 1/4 Silky.
The question asks out of 200 offspring, how many could you expect to have normal feathers?
The answer would then be 3/4 (200 normal) =
150So, the answer is
CHope that helps!
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