1) Black coat color is a dominant trait in guinea pigs. A black female guinea pig was testcrossed and produced 6 offspring, all black. What is her probable genotype? With what degree of confidence can her genotype be specified?
Answer: There's a 98.4% chance that she's BB.
2) Shorthorn cattle with the genotype CRCR are red, cattle with the CWCW genotype are white, and CRCW cattle are "roan." If roan cattle show 35% of the coloration of red cattle, and white are essentially colorless,what is the degree of dominance? Which allele is dominant?
Answer: CW (white) is dominant, D =
3) Homozygote TMTM individuals are said to have "thalassemia major" and generally die in childhood of severe anemia. Heterozygotes TMTN have "thalassemia minor," a mild anemia, and generally survive. What fraction of the adult offspring of two parents with thalassemia minor are expected to be anemic?
4) Vestigial wings and ebony body color result from independently-assorting recessive mutations in Drosophila. If a pair of VvEe flies are mated and produce 256 progeny, how many are expected to show ebony body color and normal wings?
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