In unicorns, two autosomal loci interact to determine the type of tail. One locus controls whether a tail is present at all; the allele for a tail (T) is dominant over the allele for tailless (t). If a unicorn has a tail, then alleles at a second locus (C/c) determine whether the tail is curly or straight. Farmer Baldridge has two unicorns with curly tails: when he crosses them, ½ of the progeny have curly tails, ¼ have straight tails, and ¼ do not have a tail.A)What are the genotypes of the parents at the first (T/t) locus?
The female was homozygous (TT), but the male was heterozygous (Tt)
Both were homozygous (TT)
Both were heterozygous (Tt)
The male was heterozygous (Tt), but the female was recessive (tt)
B)What are the expected phenotypes of the offspring if both parents were heterozygous for the second locus and the C allele encodes a curly tail and is dominant to the c allele, but the homozygous recessive genotype is lethal? Explain your answer.
Hint: Be sure to consider both loci. This will require you to use your answer from the previous question.Twice as many tailless offspring as curly tailed or straight tailed offspring
All of the curly tailed offspring would die
Twice as many curly tailed as straight tailed or tailless offspring
Half as many curly tailed as straight tailed or tailless offspring
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