Question

guys please help me in this question

Answer 1

Question :-

In dogs, the gene for fur color has two alleles. The dominant allele ( F ) codés for grey fur and the recessive allele ( f ) codés for black fur.

The female dog is heterozygous. The male dog is homozygous recessive. Figure out the percentage or ratio of possible phenotypes and genotypes of their puppies by using a Punnett square.

% of possible genotype :-

• FF
• Ff
• ff

% of possible phenotype :-

• Black fur
• Grey fur

Answer :-

Female dog is heterozygous i.e. it has both recessive and dominant trait.

Gene for female dog :- Ff

Male dog is homozygous recessive i.e. it has both recessive traits.

Gene for male dog :- ff

( Punnett square in the attachment )

Now, let's find genotype percentage :-

FF :- By seeing punnett square, we can say that there is no FF genes for the puppies.

So, % of FF gene = 0%

Ff :- Now, from the punnett square, There are 2 Ff alleles out of total 4.

So, % of Ff genes = 50%

ff :- There are 2 ff alleles out of 4

So, % of ff genes = 50%

Now, going on to phenotype percentage -

If the puppy has both alleles dominant or either of the allele dominant, then the puppy will have grey colour fur.

And if the puppy has both alleles recessive, then the puppy will have black colour fur.

% of black fur :- There are two genes out of 4 which have both alleles recessive.

So, % of black fur = 50%

% of grey fur :- There are two genes out of 4 which have either of the alleles dominant.

So, % of grey fur = 50%