Question: You are studying two autosomal genes regulating fur shape and color in guinea pigs. The C gene is…

You are studying two autosomal genes regulating fur shape and
color in guinea pigs. The C gene is responsible for curly fur and
the gene B for brown fur. You cross two pure lines:

-One line with curly (C) brown (B) fur—these are dominant
alleles

-Another with straight (c) white (b) fur—these are recessive
loss of function alleles

The F1 progeny are the following:

-In crosses in which the mother has curly and brown fur and the
father has straight white fur, the offspring all have straight and
brown fur

-In crosses in which the father has curly and brown fur and the
mother has straight white fur, the offspring all have curly and
white fur

a) Explain the findings (F1 progeny). Why the results are
different in the two crosses? What are the genotypes?

b) You cross a curly and white female (F1) to a straight white
fur male from the pure line. Assume the genes are 20 map units
apart. What will be the phenotypes of the progeny (F2)? Show all
the genotypes and phenotypes of the F2 progeny.

c) Would your answer to part b change if the genes were 10 map
units apart? Explain.