Question 1

True or false: During a time when resources are abundant, one would not expect much evolutionary change.

Accepted Answer

A) True 
 B)False

Question 2

Many variants are produced during the long course of an HIV infection. Which variant would be most fit in the environment of the human body?

Accepted Answer

A)  a virus that infects liver cells 
B)  a virus that reproduces very slowly 
C)  a virus that makes fewer mistakes when replicating its RNA 
D)  a virus that can't be recognized by the patient's immune system 
A)  a virus that infects liver cells 
B)  a virus that reproduces very slowly 
C)  a virus that makes fewer mistakes when replicating its RNA 
D)  a virus that can't be recognized by the patient's immune system

Question 3

What is MRSA?

Accepted Answer

A)  tuberculosis bacteria resistant to antibiotics 
B)  any bacteria resistant to antibiotics 
C)  antibiotics used as a last resort for resistant bacteria 
D)  a form of skin bacteria that's resistant to methicillin 
A)  tuberculosis bacteria resistant to antibiotics 
B)  any bacteria resistant to antibiotics 
C)  antibiotics used as a last resort for resistant bacteria 
D)  a form of skin bacteria that's resistant to methicillin

Question 4

As natural selection acts on a trait in a population, how will the amount of variation associated with that trait in the population change?

Accepted Answer

A)  Variation will decrease. 
B)  Variation will increase. 
C)  Variation will remain the same. 
D)  Variation will disappear altogether. 
A)  Variation will decrease. 
B)  Variation will increase. 
C)  Variation will remain the same. 
D)  Variation will disappear altogether.

Question 5

True or false: Natural selection is only one of several possible causes of evolution.

Accepted Answer

A) True 
 B)False

Question 6

True or false: Any trait that is controlled by genes can be acted on by natural selection.

Accepted Answer

A) True 
 B)False

Question 7

Which statement best describes the phenomenon of antibiotic resistance in bacteria?

Accepted Answer

A)  For a particular antibiotic, all bacteria are either completely resistant or completely sensitive. 
B)  When a type of bacteria is resistant to antibiotics, it's resistant to all antibiotics. 
C)  Resistance is a matter of degrees; resistance can be partial or total, and resistance to each antibiotic is a separate trait. 
D)  Resistance to antibiotics is a trait that didn't exist before antibiotics were developed for pharmaceutical use. 
A)  For a particular antibiotic, all bacteria are either completely resistant or completely sensitive. 
B)  When a type of bacteria is resistant to antibiotics, it's resistant to all antibiotics. 
C)  Resistance is a matter of degrees; resistance can be partial or total, and resistance to each antibiotic is a separate trait. 
D)  Resistance to antibiotics is a trait that didn't exist before antibiotics were developed for pharmaceutical use.

Question 8

What process could result from the natural selection explained by Darwin in his book The Origin of Species?

Accepted Answer

The answer of What process could result from the natural...

Question 9

In what way is artificial selection different from natural selection?

Accepted Answer

A)  There's no difference; both have caused evolution throughout the history of life on Earth. 
B)  Artificial selection applies to changes in domestic animals only, while natural selection applies to all other species. 
C)  In artificial selection, human preference is the selecting force; in natural selection, environmental conditions are the selecting force. 
D)  Artificial selection causes one species to change to another, while natural selection only modifies existing species. 
A)  There's no difference; both have caused evolution throughout the history of life on Earth. 
B)  Artificial selection applies to changes in domestic animals only, while natural selection applies to all other species. 
C)  In artificial selection, human preference is the selecting force; in natural selection, environmental conditions are the selecting force. 
D)  Artificial selection causes one species to change to another, while natural selection only modifies existing species.

Question 10

Which variation could be subject to natural selection?

Accepted Answer

A)  A dog with short legs due to malnutrition is able to crawl into holes better than his littermates. 
B)  A tree is not infested by a ground-dwelling beetle when the homeowner cuts the lower branches. 
C)  A hyena is born with a spotted fur pattern that allows it to hide in the grass better than its littermates. 
D)  A pigeon learns that when its keeper comes near it will get fed. 
A)  A dog with short legs due to malnutrition is able to crawl into holes better than his littermates. 
B)  A tree is not infested by a ground-dwelling beetle when the homeowner cuts the lower branches. 
C)  A hyena is born with a spotted fur pattern that allows it to hide in the grass better than its littermates. 
D)  A pigeon learns that when its keeper comes near it will get fed.

Question 11

How did an understanding of genetics lead to "the modern synthesis"?

Accepted Answer

A)  It showed how traits could be passed from one organism to the next. 
B)  It showed how many offspring a single individual was capable of producing. 
C)  It showed the extent of variation for many traits. 
D)  It showed the kind of environmental change that could cause evolution. 
A)  It showed how traits could be passed from one organism to the next. 
B)  It showed how many offspring a single individual was capable of producing. 
C)  It showed the extent of variation for many traits. 
D)  It showed the kind of environmental change that could cause evolution.

Question 12

Your text describes an experiment in which low-nutrient conditions select bacteria that would kill off other bacteria. When nutrients became plentiful again, these killer bacteria became less common because they had lower fitness in this environment, but they didn't become extinct. Why would some of the killer bacteria survive in the new environment?

Accepted Answer

A)  They're waiting for a future time when that trait may be useful again. 
B)  They have changed the killer gene to a less costly one but can regenerate the killer gene when necessary. 
C)  Competition must be low enough that the disadvantage of having the killer trait isn't great enough to cause extinction. 
D)  The killer trait is a dominant trait, so it cannot be eliminated. 
A)  They're waiting for a future time when that trait may be useful again. 
B)  They have changed the killer gene to a less costly one but can regenerate the killer gene when necessary. 
C)  Competition must be low enough that the disadvantage of having the killer trait isn't great enough to cause extinction. 
D)  The killer trait is a dominant trait, so it cannot be eliminated.

Question 13

What is an allele?

Accepted Answer

A)  a gene that has been changed by natural selection 
B)  a trait that has been influence by artificial selection 
C)  a gene that hasn't changed over time 
D)  a particular version of a gene 
A)  a gene that has been changed by natural selection 
B)  a trait that has been influence by artificial selection 
C)  a gene that hasn't changed over time 
D)  a particular version of a gene

Question 14

In 1980, only 1 to 5% of all Staphylococcus aureus isolates were MRSA strains. Now 60 to 70% of S. aureus isolates are MRSA strains. What process is the cause of this situation?

Accepted Answer

A)  stabilizing selection of humans 
B)  directional selection of humans 
C)  directional selection of bacteria 
D)  diversifying selection of bacteria 
A)  stabilizing selection of humans 
B)  directional selection of humans 
C)  directional selection of bacteria 
D)  diversifying selection of bacteria

Question 15

What kind of bacterial variant would be most likely to survive in the human digestive system?

Accepted Answer

A)  a variant that thrives at temperatures close to 100°C 
B)  a variant with a coating that is resistant to an acidic environment 
C)  a variant that reproduces slowly 
D)  a variant that easily attaches to hard surfaces 
A)  a variant that thrives at temperatures close to 100°C 
B)  a variant with a coating that is resistant to an acidic environment 
C)  a variant that reproduces slowly 
D)  a variant that easily attaches to hard surfaces

Question 16

True or false: Natural selection occurs so an organism can become perfectly adapted to its environment.

Accepted Answer

A) True 
 B)False

Question 17

Why aren't antibiotics used against the common cold?

Accepted Answer

A)  Cold viruses have already evolved resistance to antibiotics. 
B)  Colds are caused by viruses and have never been affected by antibiotics. 
C)  Antibiotics are only active against infection in the blood but not the respiratory tract. 
D)  They're only effective if you take them within the first few hours of the infection. 
A)  Cold viruses have already evolved resistance to antibiotics. 
B)  Colds are caused by viruses and have never been affected by antibiotics. 
C)  Antibiotics are only active against infection in the blood but not the respiratory tract. 
D)  They're only effective if you take them within the first few hours of the infection.

Question 18

Based on what you know about resistance to infection, why are some people resistant to HIV?

Accepted Answer

A)  They have a strong immune system that clears the virus completely. 
B)  They have been immunized in an experimental program. 
C)  They can't be infected with HIV even when exposed. 
D)  They never engage in risky behavior and thus can't become infected. 
A)  They have a strong immune system that clears the virus completely. 
B)  They have been immunized in an experimental program. 
C)  They can't be infected with HIV even when exposed. 
D)  They never engage in risky behavior and thus can't become infected.

Question 19

Which group is able to evolve?

Accepted Answer

A)  individual cats in a home 
B)  a population of asexually reproducing bacteria 
C)  a rose bush 
D)  an HIV virus that has infected a patient 
A)  individual cats in a home 
B)  a population of asexually reproducing bacteria 
C)  a rose bush 
D)  an HIV virus that has infected a patient

Question 20

True or false: The goal of natural selection is to make extreme traits more common.

Accepted Answer

A) True 
 B)False

Exam 11: An Evolving Enemy: Natural Selection

True or false: During a time when resources are abundant, one would not expect much evolutionary change.

Many variants are produced during the long course of an HIV infection. Which variant would be most fit in the environment of the human body?

What is MRSA?

As natural selection acts on a trait in a population, how will the amount of variation associated with that trait in the population change?

True or false: Natural selection is only one of several possible causes of evolution.

True or false: Any trait that is controlled by genes can be acted on by natural selection.

Which statement best describes the phenomenon of antibiotic resistance in bacteria?

What process could result from the natural selection explained by Darwin in his book The Origin of Species?

In what way is artificial selection different from natural selection?

Which variation could be subject to natural selection?

How did an understanding of genetics lead to "the modern synthesis"?

What is an allele?

In 1980, only 1 to 5% of all Staphylococcus aureus isolates were MRSA strains. Now 60 to 70% of S. aureus isolates are MRSA strains. What process is the cause of this situation?

What kind of bacterial variant would be most likely to survive in the human digestive system?

True or false: Natural selection occurs so an organism can become perfectly adapted to its environment.

Why aren't antibiotics used against the common cold?

Based on what you know about resistance to infection, why are some people resistant to HIV?

Which group is able to evolve?

True or false: The goal of natural selection is to make extreme traits more common.

Can Science Cure the Common Cold Introduction to the Scientific Method

Science Fiction, Bad Science, and Pseudoscience:

Is It Possible to Supplement Your Way to Better Performance and Health

Body Weight and Health: Enzymes, Metabolism, and Cellular Respiration

Life in the Greenhouse: Photosynthesis and Climate Change

Cancer: DNA Synthesis, Mitosis, and Meiosis

Are You Only As Smart As Your Genes Mendelian and Quantitative Genetics

DNA Detective: Complex Patterns of Inheritance and Dna Profiling

Genetically Modified Organisms: Gene Expression, Mutation,

Where Did We Come From the Evidence for Evolution

Who Am I Species and Races

The Greatest Species on Earth Biodiversity and Classification

Is the Human Population Too Large Population Ecology

Conserving Biodiversity: Community and Ecosystem Ecology

Where Do You Live Climate and Biomes

Organ Donation: Tissues and Organs

Binge Drinking: the Digestive and Urinary Systems

Clearing the Air: Respiratory and Cardiovascular Systems

Vaccination: Protection and Prevention or Peril Immune System,

Human Sex Differences: Endocrine, Skeletal, and Muscular Systems

Is There Something in the Water Reproductive and Developmental Biology

Study Drugs: Brain Boost or Brain Drain Brain Structure and Function

Feeding the World: Plant Structure and Growth

Growing a Green Thumb: Plant Physiology

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