Sickle-cell disease is caused by a recessive allele. Roughly one out of every 400 African Americans (0.25%) is afflicted with sickle-cell disease. Use the Hardy-Weinberg equation to calculate the percentage of African Americans who are carriers of the sickle-cell allele. (Hint: q2 = 0.0025.)

Determine what is incorrect in the following statement: Red deer mutated their genes so that they could have larger antlers to compete for mates.

Make a concept map (see BioSkills 12) that relates DNA's primary structure to its secondary structure. Your diagram should include deoxyribonucleotides, base-stacking interactions, purines, pyrimidines, phosphodiester linkages, DNA's primary structure, DNA's secondary structure, complementary base pairing, and antiparallel double helix.

In humans, albinism is caused by loss-of-function mutations in genes involved in the synthesis of melanin, the dark pigment in skin. Only people homozygous for a loss-of-function allele (genotype aa) have the albino phenotype. In Americans of northern European ancestry, albino individuals are present at a frequency of about 1 in 10,000 (or 0.0001). Assuming that genotypes are in Hardy–Weinberg equilibrium, what is the predicted frequency of Caucasians in the United States who carry a single allele for albinism?

If you hold a salty cracker in your mouth long enough, it will begin to taste sweet. What is responsible for this change in taste?

In the context of populations, how do we define evolution?

Allele frequencies can be altered by __________.

In the Hardy-Weinberg equation, p² represents __________.

In a large population of bonobos, the frequency of the recessive allele is initially 0.1. There is no migration and no selection. What is the frequency of the dominant allele? Assume that there are two alleles of this gene.