美联社环境科学:生态系统和生物

Study concepts, example questions & explanations for AP Environmental Science

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Example Questions

Example Question #181 :Ap Environmental Sciences

You receive a summer internship to study a rare organism of which is little is known. Through visual observation, you note that the organism is an herbivore because it only eats autotrophs. What type ofconsumeris this organism?

Possible Answers:

Tertiary consumer

Primary consumer

Quanternary consumer

Secondary consumer

The organism is not a consumer

Correct answer:

Primary consumer

Explanation:

The correct response is primary consumer. The primary consumer is any organism that eats autotrophs (photosynthetic organisms). A secondary consumer feeds on the primary consumer, and so on and so forth.

Example Question #182 :Ap Environmental Sciences

生态系统生态学家研究了解东北偏东rgy flows within ecosystems. They create food webs for interactions between producers and consumers. If an ecologist visually observes an organism that eats dead animals or fallen leaves, which type of organism are they observing?

Possible Answers:

Secondary consumer

Primary consumer

Detritivore

Tertiary consumer

Carnivore

Correct answer:

Detritivore

Explanation:

The correct response isdetritivore.Organisms classified asdetritivoresbreak down organic matter from dead animals and leaves. Primary consumers feed on autotrophs, and secondary consumers feed on primary consumers. Carnivores primarily eat meat. While detritus does contain animal matter, it also contains plant and microbial matter that carnivores tend not to eat.

Example Question #11 :Food Webs And Pyramids

Between each trophic level of a food web (for example, from producer to primary consumer), what percentage of energy islost?

Possible Answers:

50%

10%

90%

25%

33%

Correct answer:

90%

Explanation:

From one trophic level to the next, only 10% of energy is transferred. The other 90% is lost through metabolic processes, like heat. This means that for every 10,000 kcal produced by producers, a tertiary consumer (three trophic levels above) will only receive 10 kcal.

Example Question #1 :Change Due To Natural Events

Which type of erosion is caused by steady, fast flow of running water?

Possible Answers:

Splash erosion

Sheet erosion

Gully erosion

Rill erosion

Correct answer:

Gully erosion

Explanation:

All of these are caused by water in some way, however, gully erosion is due to steady and fast-flowing streams; the Grand Canyon is an excellent example of the effect of gully erosion. Splash erosion is the first step in erosion from water, and involves the breakage of soil via the impact between soil and a raindrop. It is often a precursor for other types of erosion since it loosens soil. Sheet erosion involves evenly removing a certain number of layers of material due to regular water patterns. Rill erosion is a result of small, well-defined paths of water known as rills, that flow downhill after rainfall.

Example Question #2 :Change Due To Natural Events

Climatologists work to understand what factors affect climate throughout geological time. Scientists have proposed many theories to explain complex climatic events. Which of the following theories explains how shift’s in Earth’s orbit every 100,000 years can trigger ice ages?

Possible Answers:

El Nino cycles

La Nina cycles

Milankovitch cycles

Hadley cells

Correct answer:

Milankovitch cycles

Explanation:

The correct response isMilankovitch cycles. This theory describes how the orbit, tilt, and axis of the Earth operate on a 100,000 year cycle that cause the Earth to be further from the sun. As the Earth gets farther from the sun, it can trigger an ice age. The theory is aptly named after the man who discovered it. The El Nino and La Nina events occur on a much shorter time scale and have nothing to do with ice ages.

Example Question #3 :Change Due To Natural Events

In the past 500 million years, there have been__________mass extinctions.

Possible Answers:

5

2

10

50

Correct answer:

5

Explanation:

Today, 99.9% of all species that have ever existed on Earth are extinct. We are currently in the middle of the 6th mass extinction. The dinosaurs went extinct during the 5th, the Cretaceous, about 65 million years ago.

Example Question #4 :Change Due To Natural Events

The Wallace Line is generally cited as evidence of which of the following?

Possible Answers:

Speciation

Plate tectonics

Natural Selection

Change in sea levels

Asteroid impact

Correct answer:

Change in sea levels

Explanation:

The Wallace Line, named for Alfred Russel Wallace, is a boundary that separates Asia and Australia. Wallace noticed that the some of the islands in this region contained species common to Australia and some contained species common to Asia, none of which would have crossed the open water in between the continents. Wallace correctly reasoned that this meant that sea levels were once much lower, an artifact of the last glacial maximum.

Example Question #1 :Evolution

The streamlined shape found in the body plans of both sharks and dolphins is an example of:

Possible Answers:

convergent evolution

none of these

coevolution

divergent evolution

sympatry

Correct answer:

convergent evolution

Explanation:

Sharks and dolphins are not closely related and evolved their streamlined shapes separately from one another. This is an example of convergent evolution, in which two species that are not closely related evolve similar characteristics. Divergent evolution is the opposite.

Example Question #2 :Evolution

What type of organisms were the first to develop?

Possible Answers:

Primates

Eukaryotes

Fungi

Prokaryotes

Plants

Correct answer:

Prokaryotes

Explanation:

Prokaryotes are simple, single-celled organisms which lack membrane bound nuclei. They developed before any of the other listed answer choices, as all of the other listed answer choices are multi-celled organisms that developed from prokaryotes.

Example Question #3 :Evolution

Which of the following terms is defined as any change in the proportions of different genotypes in a population from one generation to the next?

Possible Answers:

Evolution

Gene flow

Variability

Adaptation

Differential reproduction

Correct answer:

Evolution

Explanation:

Evolution is a process of orderly and gradual change or development. The theory that all living species have developed as a result of changes in their genetic material over time. Evolution is a change in the proportions of different genotypes in a population from one generation to the next. The characteristic of an organism that helps it survive and reproduce in a particular environment is adaptation. Variability is the range of alterations present in a genome, such as the number of diverse alleles of a specific gene. The differences in reproductive output among individuals of a population, normally as a result of genetic differences is differential reporduction. Gene flow is the movement of alleles from one population to another owing to the migration of individual organisms.

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