In cats an X-linked pair of alleles,
B and
b, controls color of fur. The alleles are incompletely dominant:
B produces black,
b produces yellow, and
Bb produces tortoise-shell.
| (a) | A yellow cat had a litter of two tortoiseshell kittens and one yellow. What is the sex of the yellow kitten? |
| (b) | A tortoiseshell cat brings home a litter of black, yellow, and tortoiseshell kittens. The color of which sex would tell you the color of the tomcat that produced them? |
| (c) | A yellow male is crossed with a tortoiseshell female. If the female has all male kittens in her litter of four, what color(s) would they be? |
| (d) | A tortoiseshell cat brings home her litter of black, yellow, and tortoiseshell kittens. By what method could you possibly decide whether the male parent was the black tomcat next door? |
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Phylogenetic tree based on the distribution of 120 alleles in 42 populations from around the world,
Numeric Color-Coding Systems
Color Vision
Color in Context
Controls over Digestion
Identifying ancestral versus derived alleles