Data-based question: Coat color in the house mouse
1)
1st generation
B
b
B
Bb
Bb
b
Bb
Bb
Grey = B albino=b
2nd
generation
B
b
B
BB
Bb
b
Bb
bb
Ratio between grey and albino offspring -1:3 albino:grey
2) The albino color is due to the recessive allele.When albino and grey were crossed in the
first generation, it resulted in all grey because albino is a recessive gene in those grey
mice. In second generation, it resulted in ⅓ albino mice which matches with the punnet
grid above.
3) grey=B albino=b
Male parent / B(gamete 1)B(gamete 2) grey
Female parent/ b(gamete 1)b(gamete 2) albino
B
B
b
Bb
Bb
b
Bb
Bb
The only possible combinations are Bb because the male parent has B which is the dominant
color of grey. Therefore, the offspring will all be grey.
4)
1st generation
B
b
B
Bb
Bb
b
Bb
Bb
Grey = B albino=b
2nd
generation
B
b
B
BB
Bb
b
Bb
bb
Ratio between grey and albino offspring -1:3 albino:grey
5)
The albino gene gives the entire mouse no pigment making them appear to have red
eyes while the grey mice have pigment in their fur and eyes which covers the red.