Masteringbio Chapter 23 Part 1 Study

Which of these individuals is a homozygous genotype? a. Aa b. AG c. aG d. Gg e. AA

All the genes in a population are that population's _____. a. fitness b. genotype c. gene pool d. phenotype e. Hardy-Weinberg

Genetic drift is a process based on _____. a. differential reproductive success correlated to the relationship between a phenotype and the environment b. immigration c. mutation d. emigration e. the role of chance

A mutation occurs when _____. a. there is a change in the DNA sequence of a gene b. some individuals leave more offspring than other individuals c. individuals leave a population d. population sizes are small e. individuals enter a population

Every few years a giant axe chops off the head of every person who is over 6 feet tall. How will this affect the human population? a. The mutation rate will increase. b. Alleles that promote "tallness" will decrease in frequency. c. Genetic drift will play less of a role in the evolution of humans. d. Gene flow will increase. e. It will increase in number since shorter people use fewer resources than taller people.

Modern travel along with migration reduces the probability of _____ having an effect on the evolution of humans. a. natural selection b. gene flow c. genetic drift d. mutation e. disease

The ease with which humans travel across the globe is likely to increase _____. a. natural selection b. genetic drift c. gene flow d. mutation e. all of these

Homologous pairs of chromosomes are lined up independently of other such pairs during _____. a. metaphase I b. telophase II c. prophase II d. metaphase II e. anaphase I

Crossing over, resulting in an increase in genetic variation, occurs between _____. a. nonsister chromatids of nonhomologous chromosomes b. sister chromatids of nonhomologous chromosomes c. sister chromatids of homologous chromosomes d. sex cells and somatic cells e. nonsister chromatids of homologous chromosomes

In human gamete production there is an average of _____ crossover events per chromosome pair. a. 5-6 b. 2-3 c. 10+ d. 0-1 e. 9-10

Which of these gametes contain one or more recombinant chromosomes? a. B, C, F, and G b. A, B, and C c. C, D, E, F, and G d. B, C, and G e. B, C, D, and G

This animation illustrates _____ as it occurs during _____. a. centrosome separation ... anaphase II b. crossing over ... prophase I c. random fertilization ... prophase I d. karyokinesis ... prophase II e. cytokinesis ... telophase I

Which of the following are basic components of the Hardy-Weinberg model? a .Allele frequencies, number of individuals in the population b. Frequencies of two alleles in a gene pool before and after many random matings 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. 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. b. When alleles are transmitted according to the rules of Mendelian inheritance, their frequencies do not change over time. c. Even if allele A1 is dominant to allele A2, it does not increase in frequency. d. The genotype frequencies in the offspring generation must add up to two.

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 .0.4 b. 0.5 c. 0.1 d. 80

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 0.1. b. The frequency of the A1 allele is 0.5. c. The frequency of the A1 allele is 0.7. d .The frequency of the A1 allele is 0.3.

Which of the following evolutionary forces results in adaptive changes in allele frequencies? a. Mutation b. There is no evolutionary force that results in adaptive changes in allele frequencies. c. Selection 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 0.33, 0.33, and 0.33 for A1A1, A1A2, and A2A2, 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 0.64, 0.32, and 0.04 for A1A1, A1A2, and A2A2, respectively.

Which of the following evolutionary forces could create new genetic information in a population? a. Selection b. Nonrandom mating c. Mutation d. Genetic drift