Question 1

How does gel electrophoresis allow researchers to observe genetic variation?

Accepted Answer

A) Gel electrophoresis enables a scientist to identify dominant and recessive traits. 
B) Gel electrophoresis enables scientists to identify alleles that vary. 
C) Gel electrophoresis enables scientists to replicate a strand of DNA. 
D) Gel electrophoresis enables a scientist to link phenotype to genotype. 
E) Protein gel electrophoresis enables a scientist to sequence DNA. 
A) Gel electrophoresis enables a scientist to identify dominant and recessive traits. 
B) Gel electrophoresis enables scientists to identify alleles that vary. 
C) Gel electrophoresis enables scientists to replicate a strand of DNA. 
D) Gel electrophoresis enables a scientist to link phenotype to genotype. 
E) Protein gel electrophoresis enables a scientist to sequence DNA.

Question 2

Imagine the following genotype frequencies in a population: p2 = 0.49, 2pq = 0.42, q2 = 0.09. Now assume that there is nonrandom mating where individuals with one genotype will only mate with individuals that also have their genotype. Assume this pattern of mating goes on until the frequency of heterozygotes is effectively zero. What will the frequency of allele p be in the population?

Accepted Answer

A) 0)3 
B) 0)7 
C) 0)91 
D) 0)49 
E) 1)0 
A) 0)3 
B) 0)7 
C) 0)91 
D) 0)49 
E) 1)0

Question 3

In a hypothetical population of 1000 frogs there exists a gene with two alleles. 280 of the frogs are homozygous dominant (DD), and 220 are homozygous recessive (dd). What is the frequency of heterozygotes in the population?

Accepted Answer

A) 0)0 
B) 0)28 
C) 0)22 
D) 0)50 
A) 0)0 
B) 0)28 
C) 0)22 
D) 0)50

Question 4

Which of the following statements is TRUE regarding natural populations?

Accepted Answer

A) Consistent with Thomas Malthus's hypothesis, most populations expand geometrically generation after generation. 
B) Well-established populations are typically stable in size. 
C) Resource availability generally plays no role in the size of a population. 
D) All populations evolve rapidlyF1F1F1S1F1F1F10time is rarely a factor in evolution. 
A) Consistent with Thomas Malthus's hypothesis, most populations expand geometrically generation after generation. 
B) Well-established populations are typically stable in size. 
C) Resource availability generally plays no role in the size of a population. 
D) All populations evolve rapidlyF1F1F1S1F1F1F10time is rarely a factor in evolution.

Question 5

A population experiencing genetic drift will be in Hardy-Weinberg equilibrium.

Accepted Answer

A) True 
 B)False

Question 6

A gene pool is comprised of what?

Accepted Answer

A) all the genes in a population 
B) all the alleles within a population 
C) all the individuals within a population 
D) all the offspring within a population 
A) all the genes in a population 
B) all the alleles within a population 
C) all the individuals within a population 
D) all the offspring within a population

Question 7

In contrast to positive and negative selection, _____ selection acts to maintain two or more alleles in a population.

Accepted Answer

A) balancing 
B) disruptive 
C) stabilizing 
D) directional 
A) balancing 
B) disruptive 
C) stabilizing 
D) directional

Question 8

What is the fundamental concept that causes gel electrophoresis of proteins to work?

Accepted Answer

A) Different proteins have different charges and sizes. 
B) Different proteins respond in the same way to dyes in a gel. 
C) Some proteins are enzymes and will react with molecules in the gel. 
D) All proteins have the same charge and will move through the gel at the same speed. 
E) All proteins will react with a dye to produce a band. 
A) Different proteins have different charges and sizes. 
B) Different proteins respond in the same way to dyes in a gel. 
C) Some proteins are enzymes and will react with molecules in the gel. 
D) All proteins have the same charge and will move through the gel at the same speed. 
E) All proteins will react with a dye to produce a band.

Question 9

Using visual observation of phenotypes to identify allele frequency rarely works because:

Accepted Answer

A) most alleles are recessive and will not produce a visible phenotype. 
B) phenotype is not due to the alleles. 
C) multiple genes may control the phenotype. 
D) visual phenotypes are rare. 
E) phenotype is not an indication of genotype. 
A) most alleles are recessive and will not produce a visible phenotype. 
B) phenotype is not due to the alleles. 
C) multiple genes may control the phenotype. 
D) visual phenotypes are rare. 
E) phenotype is not an indication of genotype.

Question 10

Nonadaptive mechanisms of evolutionary change are:

Accepted Answer

A) migration (gene flow), mutation, and genetic drift. 
B) migration (gene flow), balancing selection, and genetic drift. 
C) migration (gene flow), sexual selection, and genetic drift. 
D) mutation, sexual selection, and genetic drift. 
E) mutation, genetic drift, and heterozygote advantage. 
A) migration (gene flow), mutation, and genetic drift. 
B) migration (gene flow), balancing selection, and genetic drift. 
C) migration (gene flow), sexual selection, and genetic drift. 
D) mutation, sexual selection, and genetic drift. 
E) mutation, genetic drift, and heterozygote advantage.

Question 11

Consider the following two populations and the frequencies of alleles at the FGFR-1 locus. $$\begin{array} { | l | l | l | l | l | } 
\hline & \text { Allele 1 } & \text { Allele 2 } & \text { Allele 3 } & \text { Allele 4 } \
\hline \text { Population 1 } & 0.25 & 0.25 & 0.25 & 0.25 \
\hline \text { Population 2 } & 0.50 & 0.42 & 0.05 & 0.03 \
\hline
\end{array}$$ Which of the populations has greater allelic variation?

Accepted Answer

A) population 1 
B) population 2 
C) Neither, allelic diversity is the same for both populations. 
A) population 1 
B) population 2 
C) Neither, allelic diversity is the same for both populations.

Question 12

Dodos were flightless birds that have been extinct for about 300 years. Imagine that biologists found two surviving dodos on present-day Earth and mated this pair of birds. What would you expect of the resulting dodo population?

Accepted Answer

A) The maximum number of alleles present for any gene in the new population is two. 
B) Certain neutral mutations in this dodo population could become fixed, given the small population size. 
C) Adaptations will occur in this population as a result of genetic drift. 
D) Due to a population bottleneck, the frequency of alleles in this new dodo population may be very different from the frequencies expected in larger (now nonexistent)populations. 
A) The maximum number of alleles present for any gene in the new population is two. 
B) Certain neutral mutations in this dodo population could become fixed, given the small population size. 
C) Adaptations will occur in this population as a result of genetic drift. 
D) Due to a population bottleneck, the frequency of alleles in this new dodo population may be very different from the frequencies expected in larger (now nonexistent)populations.

Question 13

What is the hypothetical long-term result of different mutations accumulating in different populations?

Accepted Answer

A) the evolution of different species 
B) the extinction of one population 
C) merging the populations through migration 
D) fixation of the same alleles in both populations 
E) decreased genetic isolation 
A) the evolution of different species 
B) the extinction of one population 
C) merging the populations through migration 
D) fixation of the same alleles in both populations 
E) decreased genetic isolation

Question 14

Using protein gel electrophoresis to measure genetic variation in populations has some drawbacks. Which of the following is/are problems with the technique?

Accepted Answer

A) It can't detect synonymous mutations. That is, differences in DNA sequences that result in the same amino acid sequence can't be detected with this method. 
B) It can't detect differences in noncoding DNA. 
C) It can only be used with proteins that can be stained or otherwise labeled and visualized. 
D) It can't detect mutations that do not affect the mobility of a protein within the gel, even if the protein's amino acid sequence is changed. 
E) None of the answer options is correct. 
A) It can't detect synonymous mutations. That is, differences in DNA sequences that result in the same amino acid sequence can't be detected with this method. 
B) It can't detect differences in noncoding DNA. 
C) It can only be used with proteins that can be stained or otherwise labeled and visualized. 
D) It can't detect mutations that do not affect the mobility of a protein within the gel, even if the protein's amino acid sequence is changed. 
E) None of the answer options is correct.

Question 15

All genes have the same rate of accumulation of genetic differences.

Accepted Answer

A) True 
 B)False

Question 16

Recall that in Mendel's garden peas, the yellow gene determines flower color, with the A (yellow) allele dominant to the a (green) allele. In a population of 200 plants, the genotype frequencies are 50% AA, 25% Aa, and 25% aa. What are the allele frequencies?

Accepted Answer

A) 50% A, 50% a 
B) 50% A, 25% a 
C) 87.5% A, 12.5% a 
D) 62.5% A, 37.5% a 
E) 75% A, 25% a 
A) 50% A, 50% a 
B) 50% A, 25% a 
C) 87.5% A, 12.5% a 
D) 62.5% A, 37.5% a 
E) 75% A, 25% a

Question 17

Like natural selection, genetic drift always leads to adaptations within populations; only mutations do not result in adaptations.

Accepted Answer

A) True 
 B)False

Question 18

Migration, genetic drift, and mutation are like natural selection in that they:

Accepted Answer

A) result in evolution of a population. 
B) may alter the allele frequency in a population. 
C) may alter the genotype frequency in a population. 
D) are all methods of evolutionary change. 
E) All of these choices are correct. 
A) result in evolution of a population. 
B) may alter the allele frequency in a population. 
C) may alter the genotype frequency in a population. 
D) are all methods of evolutionary change. 
E) All of these choices are correct.

Question 19

A gene in a diploid species has five different alleles. In any one population, the allele frequencies of all five alleles must add up to:

Accepted Answer

A) one. 
B) two. 
C) five. 
D) ten. 
A) one. 
B) two. 
C) five. 
D) ten.

Question 20

Why is DNA sequencing the gold standard for measuring genetic variation?

Accepted Answer

A) It is the easiest method of identifying genetic variation. 
B) It uses mutations to detect differences in amino acid sequence. 
C) It relies on proteins instead of genetic sequence. 
D) It determines the exact genetic sequence, and thus the absolute variation in a population. 
E) It is the least accurate, and is not the gold standard. 
A) It is the easiest method of identifying genetic variation. 
B) It uses mutations to detect differences in amino acid sequence. 
C) It relies on proteins instead of genetic sequence. 
D) It determines the exact genetic sequence, and thus the absolute variation in a population. 
E) It is the least accurate, and is not the gold standard.

Exam 21: Evolution: How Genotypes and Phenotypes Change Over Time

How does gel electrophoresis allow researchers to observe genetic variation?

In a hypothetical population of 1000 frogs there exists a gene with two alleles. 280 of the frogs are homozygous dominant (DD), and 220 are homozygous recessive (dd). What is the frequency of heterozygotes in the population?

Which of the following statements is TRUE regarding natural populations?

A population experiencing genetic drift will be in Hardy-Weinberg equilibrium.

A gene pool is comprised of what?

In contrast to positive and negative selection, _____ selection acts to maintain two or more alleles in a population.

What is the fundamental concept that causes gel electrophoresis of proteins to work?

Using visual observation of phenotypes to identify allele frequency rarely works because:

Nonadaptive mechanisms of evolutionary change are:

Consider the following two populations and the frequencies of alleles at the FGFR-1 locus. Allele 1 Allele 2 Allele 3 Allele 4 Population 1 0.25 0.25 0.25 0.25 Population 2 0.50 0.42 0.05 0.03 Which of the populations has greater allelic variation?

Dodos were flightless birds that have been extinct for about 300 years. Imagine that biologists found two surviving dodos on present-day Earth and mated this pair of birds. What would you expect of the resulting dodo population?

What is the hypothetical long-term result of different mutations accumulating in different populations?

Using protein gel electrophoresis to measure genetic variation in populations has some drawbacks. Which of the following is/are problems with the technique?

All genes have the same rate of accumulation of genetic differences.

Recall that in Mendel's garden peas, the yellow gene determines flower color, with the A (yellow) allele dominant to the a (green) allele. In a population of 200 plants, the genotype frequencies are 50% AA, 25% Aa, and 25% aa. What are the allele frequencies?

Like natural selection, genetic drift always leads to adaptations within populations; only mutations do not result in adaptations.

Migration, genetic drift, and mutation are like natural selection in that they:

A gene in a diploid species has five different alleles. In any one population, the allele frequencies of all five alleles must add up to:

Why is DNA sequencing the gold standard for measuring genetic variation?

Life: Chemical, Cellular, and Evolutionary Foundations

The Molecules of Life

Nucleic Acids and Transcription

Translation and Protein Structure

Organizing Principles: Lipids, Membranes, and Cell Compartments

Making Life Work: Capturing and Using Energy

Cellular Respiration: Harvesting Energy From Carbohydrates and Other Fuel Molecules

Photosynthesis: Using Sunlight to Build Carbohydrates

Cell Signaling

Cell and Tissue Architecture: Cytoskeleton, Cell Junctions, and Extracellular Matrix

Cell Division: Variations, Regulation, and Cancer

Dna Replication and Manipulation

Genomes

Mutation and Dna Repair

Genetic Variation

Mendelian Inheritance

Inheritance of Sex Chromosomes, Linked Genes, and Organelles

The Genetic and Environmental Basis of Complex Traits

Genetic and Epigenetic Regulation

Genes and Development

Species and Speciation

Evolutionary Patterns: Phylogeny and Fossils

Human Origins and Evolution

Cycling Carbon

Bacteria and Archaea

Eukaryotic Cells: Origins and Diversity

Being Multicellular

Plant Structure and Function: Moving Photosynthesis Onto Land

Plant Reproduction: Finding Mates and Dispersing Young

Plant Growth and Development

Plant Defense: Keeping the World Green

Plant Diversity

Fungi: Structure, Function, and Diversity

Animal Nervous Systems

Animal Sensory Systems and Brain Function

Animal Movement: Muscles and Skeletons

Animal Endocrine Systems

Animal Cardiovascular and Respiratory Systems

Animal Metabolism, Nutrition, and Digestion

Animal Renal Systems: Water and Waste

Animal Reproduction and Development

Animal Immune Systems

Animal Diversity

Animal Behavior

Population Ecology

Species Interactions, Communities, and Ecosystems

Biomes and Global Ecology

The Anthropocene: Humans As a Planetary Force

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