Question

If the broad-sense heritability of a trait is .62, what proportion of the observed phenotypic variance for the trait is due to environmental influences? Assume V_GE=0.

a. 100% b. 62% c. 38% d. 0%

Use the following information to answer questions a and b:   In a certain population of genetics students at Hardy-Weinberg equilibrium, the gene for attention span has two alleles, A and a, which act in a codominant manner. Individuals of the AA genotype (blabbermouths) talk too much during lectures, whereas individuals of the aa genotype (sleepyheads) fall asleep during lectures; heterozygotes are well-behaved. At the beginning of the term, in a class of 1000 students, there are 90 sleepyheads.

a. What is the frequency of the A allele at the beginning of the term?

b. What is the frequency of heterozygotes at the beginning of the term?

Answer 1