Assume for a moment that in dogs, curly hair (C) is dominant to straight hair (c). Suppose you breed a homozygous curly hair male with a straight hair female. If mating occurred between the F1 progeny, what would be the likely F2 phenotypic ratio of hair types?

Ques 1
Assume for a moment that in dogs, curly hair (C) is dominant to straight hair (c). Suppose you breed a homozygous curly hair male with a straight hair female. If mating occurred between the F1 progeny, what would be the likely F2 phenotypic ratio of hair types? (HINT: Keep your generations straight!)
Question 2 (10 points)
In reference to the previous question, suppose you found an abandoned curly-haired dog. You don’t have access to fancy DNA instrumentation to run any fancy tests, so what might be an easier experiment you could perform to determine this dog’s genotype?
Question 3 (10 points)
In a cross involving independently assorting loci, the cross BBYY x bbyy (assume “B” and “Y” are dominant to “b” and “y,” respectively) will yield all dihybrid offspring. When those offpspring are crossed, the result is usually a 9:3:3:1 phenotypic ratio.
But what if the locus “B” and “Y” did not sort independently (i.e., they were linked, at least partially)? It would mean “BY” and “by” are now more likely. How would this specifically affect the expected 9:3:3:1 ratio? To be more clear, which one of these numbers in the ratio (9, 3, 3, and/or 1) would be expected to decrease?
Question 3 options:
the 9 would decrease
the 1 would decrease
both 3’s would decrease
one of the 3’s would decrease
Question 4 (10 points)
Perform the same starting cross you did in the previous question. But this time, perform a test cross (x bbyy) as your second cross. This would result in an expected ratio of 1:1:1:1. How would this ratio be expected to change if the two loci did not sort independently?
Question 4 options:
recombinants would decrease
recombinants would increase
parentals would increase
parentals would decrease

Question 5 (10 points)
If you have a dihybrid organism with genotype AaBb whose alleles are in repulsion (trans) configuration, and you use it to perform a test cross, what will be the recombinant genotypes in the offpsring? Select all that apply.
Question 5 options:
aabb
Aabb
aaBb
AaBb
Question 7 (10 points)
In flies, assume black (B) is dominant and green (b) is recessive for abdomen color, and straight (S) is dominant and bent (s) is recessive for antenna shape. Assume also that these genes are found on the same chromosome. If single mutants for each of these genes (green abdomen x bent antenna) are crossed with one another, and you then testcross the resulting offspring, you get the following numbers of each phenotype:
black, straight 17
green, bent 12
black, bent 337
green, straight 364
What is the map distance between B and S? You must show and clearly label ALL work to receive credit.

Question 8 (10 points)
Consider the map distance you just calculated in the previous question. If a green abdomen, bent antenna double mutant fly was crossed with a wild type, and you then used their offspring for a testcross, what phenotypic ratio would you expect to see in the F2?
Question 9 (10 points)
Suppose a man carries a very uncommon dominant mutation for a deadly muscular disease that doesn’t show up until people are usually over 50 years of age (he has the disease). He and his wife are expecting their first child–a girl. What is the probability she will also have the disease if…
(1) it is autosomal
(2) it is X-linked
(3) it is Y-linked
Explain each answer in detail. Assume the penetrance of the trait is 100%.

Question 10 (10 points)
Using the Rich Text Editor to create your tables, in the text box below, draw Punnet squares representing the two crosses shown in Chapter 20, Figure 165.

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