Question 1

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

Accepted Answer

The human digestive system has an acidic environment, especially in the stomach. Bacteria with a coating that is resistant to acidity would be more likely to survive in such an environment.

Question 2

Which of the following is NOT part of the theory of natural selection?
A) Individuals in a population vary.
B) Some variation can be passed on to offspring.
C) Populations produce more offspring than the environment can support.
D) All species are descended from a common ancestor.

Accepted Answer

The theory of natural selection deals with how individuals with advantageous traits are more likely to survive and reproduce, leading to those traits becoming more common in a population over time. The idea that all species are descended from a common ancestor is more closely related to the theory of evolution, but not specifically to natural selection.

Question 3

What is the primary body part affected by tuberculosis?
A) the liver
B) the muscles
C) the immune system
D) the lungs

Accepted Answer

Tuberculosis primarily affects the lungs, although it can also affect other parts of the body such as the kidneys, spine, and brain.

Question 4

How is tuberculosis transmitted?
A) by sexual contact
B) by contaminated food
C) by sneezes
D) by infected blood products

Accepted Answer

Tuberculosis is primarily transmitted through the air when an infected person coughs, sneezes, speaks, or sings, which releases tiny droplets containing the bacteria. The bacteria can then be inhaled by others and potentially cause infection. Sexual contact and contaminated food are not common modes of transmission for tuberculosis. While tuberculosis can potentially be transmitted through infected blood products, this is extremely rare with modern screening and testing methods.

Question 5

Any individual organism has the potential to evolve if it's given enough time and possesses a mechanism to generate variation.

Accepted Answer

Evolution occurs at the population level, not at the level of individual organisms. Individuals do not evolve; populations do, through changes in allele frequencies over generations.

Question 6

In order for the theory of common descent and the theory of natural selection to both be true, what can we infer about the genetic material for all life?
A) It must change very rarely.
B) It must vary spontaneously and randomly.
C) It must be transferrable between adults.
D) It must be transferable between different species.

Accepted Answer

The theory of common descent suggests that all life on Earth shares a common ancestor, which means that all genetic material must have been passed down from that ancestor. The theory of natural selection suggests that the variations in genetic material provide the foundation for evolution, which means that genetic material must vary spontaneously and randomly. So, in order for both theories to be true, genetic material must vary spontaneously and randomly.

Question 7

Darwin explained in his book The Origin of Species how natural selection could result in ________.

Accepted Answer

The answer of Darwin explained in his book The Origin...

Question 8

Your friend was diagnosed with strep throat 2 months ago. She was treated with antibiotics for 10 days, but 2 weeks after treatment, the symptoms returned. She was given a different antibiotic and her symptoms improved again, initially, but then got worse. What is happening?
A) Your friend has taken antibiotics so long that she has become tolerant to them, making them ineffective.
B) Exposure to antibiotics has caused each individual bacterial cell to evolve resistance to the antibiotics.
C) Your friend was originally infected with some bacteria that were resistant to these two antibiotics and the bacteria multiplied.
D) Your friend probably doesn't have a bacterial infection. There must be some other reason for her symptoms.

Accepted Answer

It is possible that the original infection was caused by bacteria that were resistant to the first two antibiotics prescribed, and these bacteria continued to multiply despite treatment, leading to a recurrence of symptoms. A culture and sensitivity test could be done to determine which antibiotics are most effective against the specific bacteria causing the infection.

Question 9

When a population of organisms is evolving, what can you be sure is happening?
A) It's improving.
B) It's stable (no change).
C) It's getting bigger.
D) It's changing.

Accepted Answer

When a population of organisms is evolving, it means it's changing. Evolution is the process of change in all forms of life over generations. It does not necessarily mean that the population is improving or getting bigger, and it also may not be stable (no change).

Question 10

After a rapid change in climate, one population of bird quickly adapts to the change, but others in the area do not. What could you conclude about the quickly adapting population?
A) They had a greater need to evolve than the other population.
B) They already had some alleles in their genome that were adaptive in the new environment.
C) They reproduced more slowly than the non-adapting population.
D) They had a higher rate of mutation than the other population.

Accepted Answer

The fact that this population quickly adapted to the change suggests that they already had some alleles in their genome that were adaptive in the new environment. This could be due to prior exposure to similar environmental conditions or random chance mutation that proved beneficial in the new environment.

Question 11

A city was intensively sprayed with DDT to control houseflies. The number of houseflies was immediately greatly reduced. Each year thereafter, the city was sprayed again, but the flies gradually increased in numbers until 10 years later, when they were almost as abundant as they were when the control program began. Which of the following most likely explains this?
A) Flies from other areas moved in and replaced the ones killed by DDT.
B) The few flies that were affected by DDT but survived developed antibodies to DDT, which they passed on to their descendants.
C) The DDT caused new mutations to occur in the surviving flies, resulting in resistance to DDT.
D) The DDT killed most flies. The few that were already naturally resistant survived and passed this resistance on to their offspring.

Accepted Answer

The most likely explanation is natural selection resulting in the survival and reproduction of DDT-resistant individuals. These resistant individuals would have passed on their genes for resistance to their offspring, leading to an increasing proportion of resistant flies in the population over time. This process is an example of natural selection, where individuals with advantageous traits are more likely to survive and reproduce. Options A, B, and C are less likely explanations, as they all require unlikely scenarios such as large-scale migration of flies from other areas or rapid development of resistance through mutations or antibody production.

Question 12

What causes the disease tuberculosis?
A) a particular type of virus
B) a particular type of bacteria
C) exposure to polluted air
D) genetics

Accepted Answer

Tuberculosis is caused by a particular type of bacteria called Mycobacterium tuberculosis. It can spread from person to person through the air when someone with active tuberculosis coughs or sneezes.

Question 13

Which of the following variations could be subject to natural selection?
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.

Accepted Answer

Natural selection acts on heritable traits that affect an organism's fitness. The spotted fur pattern in the hyena is a genetic trait that can be passed on to offspring and affects its ability to survive and reproduce.

Question 14

Evolution is
A) a rare event.
B) constantly occurring at the same rate in all organisms.
C) a process that occurs as a result of differences in reproductive fitness.
D) a process that occurred only in the past.

Accepted Answer

Evolution is a process that occurs as a result of differences in reproductive fitness, where individuals with advantageous traits are more likely to survive and reproduce, passing those traits to their offspring. It is a constant and ongoing process that happens in all organisms, not just a rare event. And it is not something that only occurred in the past, as it continues to occur today.

Question 15

Which of the following is able to evolve?
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

Accepted Answer

A population of asexually reproducing bacteria is able to evolve through mutations and natural selection. Individual cats, a rose bush, and a specific HIV virus are not able to evolve on their own.

Question 16

You notice that some squirrels in your neighborhood have a much darker coat color than most of the other squirrels. Is this darker color an adaptation?
A) Yes, all variations are adaptations.
B) No, adaptations are traits developed when they're needed to help an organism survive.
C) You can't know unless you can know the coat color of the dark squirrel's parents.
D) The trait is only an adaptation if it gives the squirrels an advantage in their habitat.

Accepted Answer

The definition of an adaptation is a trait that gives an organism an advantage in its environment. Without knowing if the darker coat color provides any advantage, we cannot definitively say whether it is an adaptation or not. Therefore, option D is the best choice as it highlights the condition under which the darker coat color can be considered as an adaptation.

Question 17

Natural selection is only one of several possible causes of evolution.

Accepted Answer

Natural selection is one mechanism of evolution, but other causes include genetic drift, gene flow, mutation, and non-random mating.

Question 18

If you wanted to see natural selection working in a population of mosquitoes in response to pesticide, how much pesticide should you use?
A) Enough to kill most but not all the mosquitoes.
B) Enough to kill all the mosquitoes.
C) Just enough so that the mosquitoes will be exposed but not enough to kill any of them.
D) Enough to kill the weakest 1% of the mosquitoes.

Accepted Answer

To see natural selection in action, enough pesticide should be used to kill most but not all of the mosquitoes. This will allow the fittest individuals to survive and reproduce, leading to the evolution of pesticide resistance in the population over time. Using too little pesticide may not produce a strong enough selection pressure, while using too much pesticide will kill off the entire population, preventing any further evolution.

Question 19

Traits that increase fitness in a particular environment are called ________.

Accepted Answer

The answer of Traits that increase fitness in a particular...

Question 20

Which of the following describes natural selection?
A) A population of a mammal species varies in the length of their legs; water levels rise and the habitat becomes swampy; the individuals with shorter legs are better able to swim to food; the population evolves to become shorter-legged.
B) A population of a mammal species lives near the water; water levels rise and the habitat becomes swampy; the animals have trouble moving in the water; the population changes to a shorter-legged type so they can move more easily in the water.
C) Water levels rise and a habitat becomes swampy; a population of a mammal species on high ground observes the change; individuals with shorter legs migrate to the area.
D) A population of a mammal species lives near the water; water levels rise and the habitat becomes swampy; the act of swimming shortens the legs of the mammals; the offspring of the mammal species have shorter legs.

Accepted Answer

Natural selection is the process by which organisms with certain advantageous traits are more likely to survive and reproduce than those without those traits. In this scenario, the individuals with shorter legs are better able to swim and therefore have an advantage over those with longer legs. As a result, they are more likely to survive and reproduce, passing on their shorter-legged trait to future generations.

Quiz 11: An Evolving Enemy: Natural Selection

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

Which of the following is NOT part of the theory of natural selection?

What is the primary body part affected by tuberculosis?

How is tuberculosis transmitted?

Any individual organism has the potential to evolve if it's given enough time and possesses a mechanism to generate variation.

In order for the theory of common descent and the theory of natural selection to both be true, what can we infer about the genetic material for all life?

Darwin explained in his book The Origin of Species how natural selection could result in ________.

Your friend was diagnosed with strep throat 2 months ago. She was treated with antibiotics for 10 days, but 2 weeks after treatment, the symptoms returned. She was given a different antibiotic and her symptoms improved again, initially, but then got worse. What is happening?

When a population of organisms is evolving, what can you be sure is happening?

After a rapid change in climate, one population of bird quickly adapts to the change, but others in the area do not. What could you conclude about the quickly adapting population?

What causes the disease tuberculosis?

Which of the following variations could be subject to natural selection?

Evolution is

Which of the following is able to evolve?

You notice that some squirrels in your neighborhood have a much darker coat color than most of the other squirrels. Is this darker color an adaptation?

Natural selection is only one of several possible causes of evolution.

If you wanted to see natural selection working in a population of mosquitoes in response to pesticide, how much pesticide should you use?

Traits that increase fitness in a particular environment are called ________.

Which of the following describes natural selection?