Could you please help me solve this question? I really have no idea how to solve it, I've tried everything I know. I cannot get the right ratios.
Thanks a lot in advance!
I would also appreciate a way to approach the problem, not just the right answers.
The fur of hamsters can be described as bristly, curly, wavy or smooth. Your great aunt Maribel
dies and leaves you her two hamsters, one of which has a bristly coat, while the other has a wavy
coat. Because hamsters are prolific breeders, you soon have more than 20 hamsters with a coat
type distribution as follows (remember, all of these progeny have the same parents): 11 bristly,
10 curly. You take two of the curly offspring and mate them to each other repeatedly, obtaining
18 curly and16 wavy furred hamsters. You take two different curly offspring (of the original
pair), and do the same thing; this time you get 14 curly offspring and 15 smooth offspring. Now
you have to stop, because you are overrun with hamsters.
So:
4 traits: Bristly, Curly, Wavy and Smooth
P Bristly x Wavy
F1
11 bristly
10 curly
F2(1) Curly x Curly (from F1)
18 curly
16 wavy
F2(2) Curly x Curly (from F1)
14 Curly
15 smooth
1. Which of the following best describes the genotype of the original bristly parent?
a) B/B
b) B/b
c) B/b; w/w
d) B/b; W/w
e) none of the above
2. If you crossed the original bristly parent to one of its smooth-haired grandchildren, what ratio
would you expect in the offspring?
a) all bristly
b) ½ bristly, ½ smooth
c) ½ bristly, ½ wavy
d) ½ bristly, ½ curly
e) 1/4 bristly, 1/4 curly, 1/4 wavy, 1/4 smooth
3. The genetic basis of fur texture in hamsters is best described as:
a) two interacting genes
b) two linked genes
c) one gene with incomplete penetrance
d) one gene with incomplete dominance
e) one gene with multiple alleles
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