Question

Suppose a pigeon that is homozygous for the no group allele mates with a heterozygous pigeon. what is the expected frequency of the homozygous no grouse genotype in the offspring?

Answer 1

When a homozygous pigeon ('gg') mates with a heterozygous pigeon ('Gg'), the expected frequency of offspring that are homozygous no grouse ('gg') is 50%, which can be visualized using a Punnett square.

Step-by-step explanation:

When a pigeon that is homozygous for the no grouse allele (let's call this allele 'g' for grouse) mates with a heterozygous pigeon ('Gg'), the expected frequency of the homozygous no grouse genotype ('gg') in the offspring can be determined by using a Punnett square.

To create the Punnett square, we list the alleles of one parent across the top and the alleles of the other parent down the side. For this cross, one parent is 'gg' and the other is 'Gg'. The possible allele combinations can be represented as follows:

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Now we can construct the Punnett square:

g g

G Gg Gg

g gg gg

As shown in the Punnett square, 50% of the offspring will be heterozygous (Gg) and 50% will be homozygous no grouse (gg). Therefore, the expected frequency of the homozygous no grouse genotype ('gg') among the offspring is 50%, or 1 in 2.