AP Environmental Science : Change Due to Natural Events

Study concepts, example questions & explanations for AP Environmental Science

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Example Questions

Example Question #74 : Ecosystems And Biology

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

Possible Answers:

Gully erosion

Sheet erosion

Splash 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 #75 : Ecosystems And Biology

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:

La Nina cycles

Hadley cells

El Nino cycles

Milankovitch cycles

Correct answer:

Milankovitch cycles

Explanation:

The correct response is Milankovitch 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 #1 : Change Due To Natural Events

In the past 500 million years, there have been __________ mass extinctions.

Possible Answers:

10

50

5

2

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 #76 : Ecosystems And Biology

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

Possible Answers:

Change in sea levels

Plate tectonics

Speciation

Natural Selection

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.

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