Question 1

Speciation occurs

Accepted Answer

A) after populations become reproductively isolated and diverge. 
B) when mutations generate observable differences. 
C) when transitional forms develop between different populations. 
D) when natural selection pressures reach their maximum. 
E) with all of these. 
A) after populations become reproductively isolated and diverge. 
B) when mutations generate observable differences. 
C) when transitional forms develop between different populations. 
D) when natural selection pressures reach their maximum. 
E) with all of these.

Question 2

Speciation caused by a change in the course of a river is an example of __________ speciation.

Accepted Answer

A) divergent 
B) parapatric 
C) allopatric 
D) convergent 
E) sympatric 
A) divergent 
B) parapatric 
C) allopatric 
D) convergent 
E) sympatric

Question 3

What feature of the island of Hawaii, after its formation, most spurred the rapid speciation of colonizing birds?

Accepted Answer

A) diversity of habitats 
B) lack of competitors 
C) climate conditions 
D) abundance of plant food sources 
E) abundance of insects for food 
A) diversity of habitats 
B) lack of competitors 
C) climate conditions 
D) abundance of plant food sources 
E) abundance of insects for food

Question 4

Human infants of low or very high birth weights are less likely to survive than those of average weight.This outcome is an example of __________ selection.

Accepted Answer

A) directional 
B) stabilizing 
C) balanced polymorphism 
D) disruptive 
E) gender 
A) directional 
B) stabilizing 
C) balanced polymorphism 
D) disruptive 
E) gender

Question 5

Of 400 people who dwell on a Pacific island, 16 are homozygous recessive for a trait that has only two different types of alleles in the population.The number of heterozygous people is

Accepted Answer

A) 256. 
B) 32. 
C) 64. 
D) 128. 
E) 384. 
A) 256. 
B) 32. 
C) 64. 
D) 128. 
E) 384.

Question 6

Which of the following is a source of new alleles within a population?

Accepted Answer

A) genetic recombination 
B) meiosis 
C) mutation 
D) genetic drift 
E) natural selection 
A) genetic recombination 
B) meiosis 
C) mutation 
D) genetic drift 
E) natural selection

Question 7

Which of the following is a type of reproductive isolating mechanism?

Accepted Answer

A) temporal isolation 
B) mechanical isolation 
C) behavioral isolation 
D) ecological isolation 
E) all of these 
A) temporal isolation 
B) mechanical isolation 
C) behavioral isolation 
D) ecological isolation 
E) all of these

Question 8

Postzygotic reproductive isolation occurs

Accepted Answer

A) just after the union of the egg and sperm nuclei. 
B) during embryo development. 
C) during fetal development. 
D) after birth. 
E) with any of these. 
A) just after the union of the egg and sperm nuclei. 
B) during embryo development. 
C) during fetal development. 
D) after birth. 
E) with any of these.

Question 9

Reproductive isolating mechanisms are

Accepted Answer

A) specific behaviors that allow males to compete against other males for females. 
B) the processes by which sexual selection evolves within a population. 
C) the ways that gene flow is blocked between populations. 
D) the ways in which individuals within a species are unable to produce fertile offspring. 
E) the various geographic barriers to immigration and emigration of individuals between populations. 
A) specific behaviors that allow males to compete against other males for females. 
B) the processes by which sexual selection evolves within a population. 
C) the ways that gene flow is blocked between populations. 
D) the ways in which individuals within a species are unable to produce fertile offspring. 
E) the various geographic barriers to immigration and emigration of individuals between populations.

Question 10

Male mallards have had emerald green head feathers and wings with metallic blue patches for hundreds of years, whereas female mallards have been drab, brown-feathered ducks.This phenotypic situation suggests that mallards may be an example of

Accepted Answer

A) directional selection. 
B) polyploidy. 
C) allopatric speciation. 
D) disruptive selection. 
E) sexual selection 
A) directional selection. 
B) polyploidy. 
C) allopatric speciation. 
D) disruptive selection. 
E) sexual selection

Question 11

The Hardy-Weinberg formula is valuable for the calculation of changes in

Accepted Answer

A) population size. 
B) speciation. 
C) allele frequencies. 
D) mutation. 
E) dimorphism. 
A) population size. 
B) speciation. 
C) allele frequencies. 
D) mutation. 
E) dimorphism.

Question 12

Immigration of individuals into a population in Hardy-Weinberg equilibrium will NOT alter the equilibrium if

Accepted Answer

A) they are beyond the age of reproduction. 
B) females and males are in equal proportions. 
C) they mate randomly in the new population. 
D) they arrive in large numbers. 
E) they bring their offspring with them. 
A) they are beyond the age of reproduction. 
B) females and males are in equal proportions. 
C) they mate randomly in the new population. 
D) they arrive in large numbers. 
E) they bring their offspring with them.

Question 13

Which statement is NOT true?

Accepted Answer

A) Migration leads to genetic variation. 
B) Dominant genes always occur more frequently in a population than recessive genes. 
C) Nonrandom mating may result in changes in gene frequency. 
D) The Hardy-Weinberg law applies to large, stable populations. 
E) Crossing over increases variation. 
A) Migration leads to genetic variation. 
B) Dominant genes always occur more frequently in a population than recessive genes. 
C) Nonrandom mating may result in changes in gene frequency. 
D) The Hardy-Weinberg law applies to large, stable populations. 
E) Crossing over increases variation.

Question 14

The influence of genetic drift on allele frequencies increases as

Accepted Answer

A) gene flow increases. 
B) population size decreases. 
C) mutation rate decreases. 
D) the number of heterozygous loci increases. 
E) random mating increases. 
A) gene flow increases. 
B) population size decreases. 
C) mutation rate decreases. 
D) the number of heterozygous loci increases. 
E) random mating increases.

Question 15

Sexual dimorphism has arisen as a result of

Accepted Answer

A) stabilizing selection. 
B) heterozygote superiority. 
C) kin selection. 
D) sexual selection. 
E) directional selection. 
A) stabilizing selection. 
B) heterozygote superiority. 
C) kin selection. 
D) sexual selection. 
E) directional selection.

Question 16

Whether a mutation is ultimately considered harmful, neutral, or lethal is often determined by

Accepted Answer

A) phenotype. 
B) the will of the individual. 
C) the Hardy-Weinberg formula. 
D) environment. 
E) fate. 
A) phenotype. 
B) the will of the individual. 
C) the Hardy-Weinberg formula. 
D) environment. 
E) fate.

Question 17

This graph shows both human birth weight and newborn infant mortality.The most common birth weight is between seven and eight pounds.Human birth weight seems to be an example of

Accepted Answer

A) directional selection.   
B) stabilizing selection. 
C) sexual selection. 
D) disruptive selection. 
E) artificial selection. 
A) directional selection.   
B) stabilizing selection. 
C) sexual selection. 
D) disruptive selection. 
E) artificial selection.

Question 18

Two individuals are members of the same species if they

Accepted Answer

A) possess the same number of chromosomes. 
B) breed at the same time. 
C) are phenotypically indistinguishable. 
D) can mate and produce fertile offspring. 
E) occupy the same habitat. 
A) possess the same number of chromosomes. 
B) breed at the same time. 
C) are phenotypically indistinguishable. 
D) can mate and produce fertile offspring. 
E) occupy the same habitat.

Question 19

Hybrid inviability is the result of what kind of reproductive isolation?

Accepted Answer

A) gamete mortality 
B) prezygotic 
C) behavioral 
D) mechanical 
E) postzygotic 
A) gamete mortality 
B) prezygotic 
C) behavioral 
D) mechanical 
E) postzygotic

Question 20

New alleles arise by

Accepted Answer

A) mutation. 
B) migration. 
C) genetic drift. 
D) random mating. 
E) independent assortment. 
A) mutation. 
B) migration. 
C) genetic drift. 
D) random mating. 
E) independent assortment.

Exam 18: Emergence of Evolutionary Thought

Speciation occurs

Speciation caused by a change in the course of a river is an example of __________ speciation.

What feature of the island of Hawaii, after its formation, most spurred the rapid speciation of colonizing birds?

Human infants of low or very high birth weights are less likely to survive than those of average weight.This outcome is an example of __________ selection.

Of 400 people who dwell on a Pacific island, 16 are homozygous recessive for a trait that has only two different types of alleles in the population.The number of heterozygous people is

Which of the following is a source of new alleles within a population?

Which of the following is a type of reproductive isolating mechanism?

Postzygotic reproductive isolation occurs

Reproductive isolating mechanisms are

Male mallards have had emerald green head feathers and wings with metallic blue patches for hundreds of years, whereas female mallards have been drab, brown-feathered ducks.This phenotypic situation suggests that mallards may be an example of

The Hardy-Weinberg formula is valuable for the calculation of changes in

Immigration of individuals into a population in Hardy-Weinberg equilibrium will NOT alter the equilibrium if

Which statement is NOT true?

The influence of genetic drift on allele frequencies increases as

Sexual dimorphism has arisen as a result of

Whether a mutation is ultimately considered harmful, neutral, or lethal is often determined by

This graph shows both human birth weight and newborn infant mortality.The most common birth weight is between seven and eight pounds.Human birth weight seems to be an example of

Two individuals are members of the same species if they

Hybrid inviability is the result of what kind of reproductive isolation?

New alleles arise by

Invitation to Biology

Lifes Chemical Basis

Molecules of Life

Cell Structure and Function

A Closer Look at Cell Membranes

Ground Rules of Metabolism

Where It Startsphotosynthesis

Energy-Releasing Pathways

How Cells Reproduce

Meiosis and Sexual Reproduction

Observing Patterns in Inherited Traits

Chromosomes and Human Inheritance

Dna Structure and Function

From Dna to Protein

Controls Over Genes

Recombinant Dna and Genetic Engineering

The Macroevolutionary Puzzle

Organizing Information About Species

The Origin and Evolution of Life

Viruses and Prokaryotes

Protists the Simplest Eukaryotes

Plants

Fungi

Animals: the Invertebrates

Animal Evolution the Chordates

Human Evolution: a Case Study

Plant Tissues

Plant Nutrition and Transport

Plant Reproduction

Plant Growth and Development

Animal Tissues and Organ Systems

Neural Control

Sensory Perception

Endocrine Control

Protection, Support, and Movement

Circulation

Immunity

Respiration

Digestion and Human Nutrition

Maintaining the Internal Environment

Animal Reproductive Systems

Animal Development

Animal Behavior

Population Ecology

Community Structure and Biodiversity

Ecosystems

The Biosphere

Human Impacts on the Biosphere

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