BIOL 1202 Chapter 23 Quiz 2

Which of the following are basic components of the Hardy-Weinberg model? A. Frequencies of two alleles in a gene pool before and after many random mating's B. Allele frequencies, number of individuals in the population C. Allele frequencies in a subset of the population D. Allele frequencies, phenotype frequencies

Which of the following statements is not a part of the Hardy-Weinberg principle? A. The genotype frequencies in the offspring generation must add up to two. B. If allele frequencies in a population are given by p and q, then genotype frequencies will be given by p2, 2pq, and q2 for generation after generation. C. When alleles are transmitted according to the rules of Mendelian inheritance, their frequencies do not change over time. D. Even if allele A1 is dominant to allele A2, it does not increase in frequency.

True or false? The Hardy-Weinberg model makes the following assumptions: no selection at the gene in question; no genetic drift; no gene flow; no mutation; random mating. A. True B. False

What is the frequency of the A1A2 genotype in a population composed of 20 A1A1 individuals, 80 A1A2 individuals, and 100 A2A2 individuals? A. 0.1 B. 80 C. 0.4 D. 0.5

What is the frequency of the A1 allele in a population composed of 20 A1A1 individuals, 80 A1A2 individuals, and 100 A2A2 individuals? A. The frequency of the A1 allele is 0.5. B. The frequency of the A1 allele is 0.3. C. The frequency of the A1 allele is 0.7. D. The frequency of the A1 allele is 0.1

Which of the following evolutionary forces results in adaptive changes in allele frequencies? A. Selection B. There is no evolutionary force that results in adaptive changes in allele frequencies. C. Mutation D. Nonrandom mating

What genotype frequencies are expected under Hardy-Weinberg equilibrium for a population with allele frequencies of p = 0.8 and q = 0.2 for a particular gene? A. The expected genotype frequencies are 0.64, 0.32, and 0.04 for A1A1, A1A2, respectively. B. The expected genotype frequencies are 0.32, 0.64, and 0.04 for A1A1, A1A2, and A2A2, respectively. C. The expected genotype frequencies are 0.25, 0.5, and 0.25 for A1A1, A1A2, and A2A2, respectively. D. The expected genotype frequencies are 0.33, 0.33, and 0.33 for A1A1, A1A2, and A2A2, respectively.

Which of the following evolutionary forces could create new genetic information in a population? A. Nonrandom mating B. Selection C. Genetic drift D. Mutation

Which type of selection tends to increase genetic variation? A. Stabilizing selection B. Disruptive selection C. Directional selection

In a bell-shaped curve, the x-axis (horizontal direction) of the graph represents which of the following? A. The value of a particular characteristic; characteristics of an organism can include such traits as size and color. B. The number of individuals C. Time

True or false? Heterozygote advantage refers to the tendency for heterozygous individuals to have better fitness than homozygous individuals. This higher fitness results in less genetic variation in the population. A. True B. False

Long necks make it easier for giraffes to reach leaves high on trees, while also making them better fighters in "neck wrestling" contests. In both cases, which kind of selection appears to have made giraffes the long-necked creatures they are today? A. Directional selection B. Stabilizing selection C. Disruptive selection

Women often have complications during labor while giving birth to very large babies, whereas very small babies tend to be underdeveloped. Which kind of selection is most likely at work regarding the birth weight of babies? A. Stabilizing selection B. Directional selection C. Disruptive selection

Black-bellied seed-crackers have either small beaks (better for eating soft seeds) or large beaks (better for hard seeds). There are no seeds of intermediate hardness; therefore, which kind of selection acts on beak size in seed-crackers? A. Directional selection B. Disruptive selection C. Stabilizing selection

Small Aristelliger lizards have difficulty defending territories, but large lizards are more likely to be preyed upon by owls. Which kind of selection acts on the adult body size of these lizards? A. Disruptive selection B. Directional selection C. Stabilizing selection