Campbell Biology 11th Edition by Lisa Urry,Michael Cain,Steven Wasserman,Peter Minorsky,Jane Reece

Exercise 11

Using the Hardy-Weinberg Equation to Interpret Data and Make Predictions
Is Evolution Occurring in a Soybean Population One way to test whether evolution is occurring in a population is to compare the observed genotype frequencies at a locus with those expected for a nonevolving population based on the Hardy-Weinberg equation. In this exercise, you'll test whether a soybean population is evolving at a locus with two alleles, C G and C Y , that affect chlorophyll production and hence leaf color.
How the Experiment Was Done Students planted soybean seeds and then counted the number of seedlings of each genotype at day 7 and again at day 21. Seedlings of each genotype could be distinguished visually because the C G and C Y alleles show incomplete dominance: C G C G seedlings have green leaves, C G C Y seedlings have green-yellow leaves, and C Y C Y seedlings have yellow leaves.
Use the observed genotype frequencies from the day 7 data to calculate the frequencies of the C G allele (p) and the C Y allele (q). (Remember that the frequency of an allele in a gene pool is the number of copies of that allele divided by the total number of copies of all alleles at that locus.)