Concept explainers
The frequency of tasters and nontasters of PTC (see Problem
a. Calculate the frequency of the dominant (T) allele for PTC tasting and the recessive (t) allele for nontasting in each population.
b. Assuming that Hardy
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- For each of the following characteristics, indicate whether it would be considered a discontinuous characteristic or a quantitative characteristic. Briefly justify your answer. a. Kernel color in a strain of wheat, in which two codominant alleles segregating at a single locus determine the color. Thus, there are three phenotypes present in this strain: white, light red, and medium red. b. Body weight in a family of Labrador retrievers. An autosomal recessive allele that causes dwarfism is present in this family. Two phenotypes are recognized: dwarf (less than 13 kg) and normal (greater than 23 kg). c. Presence or absence of leprosy. Susceptibility to leprosy is determined by multiple genes and numerous environmental factors. d. Number of toes in guinea pigs, which is influenced by genes at many loci. e. Number of fingers in humans. Extra (more than five) fingers are caused by the presence of an autosomal dominant allele.arrow_forwardUsing the example of pea color in Mendel’s pea plants, can you devise equations to determine the allele frequencies of A and a from the genotype frequencies of aa, Aa, and AA?arrow_forwardThe Valyrian elders are doing projections about the future and want to calculate the frequencies of certain genotypes in the next generation. They are only interested in figuring out what proportion of the next generation will bear the signature Valyrian silver hair phenotype. (Assume the allele frequencies remain unchanged from the first part of this question.) A-What will the frequency of the AA genotype be? b-What will the frequency of the Aa genotype be?arrow_forward
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