a common recessive trait in dogs is deafness. homozygous line of normal-hearing dogs was crossed with a homozygous line of deaf dogs. F1 and F2 generations were produced. What % of F1 generation is expected to have normal hearing? What is a phenoeyeic ratio of the F2 generation?

5 answers

Let:

D=normal
and
d=recessive

P1:

DD x Dd

F1:

1DD : 2Dd : 1dd

66% should have normal hearing.

The second question is incomplete.
I should have said 75%, but the second question still can not be answered.
You’re answer is wrong because if they’re both homozygous parents, one dominant and one recessive, their genotypes would be DD x dd
What is the answer
For his 2nd Experiment, Gregor Mendel self-fertilized plants from the First generation to produce the second generation. However, dogs can’t self-fertilize. So you should use two offspring from the first generation to produce the second generation.