OG Test 3 - Reading 3

Questions 23-33 are based on the following passage.

Environmentalist Otters

It has long been known that the sea otters 23living along the West Coast of North America help keep kelp forests in their habitat healthy and vital. They do this by feeding on sea urchins and other herbivorous invertebrates that graze voraciously on kelp. With sea otters to keep the population of sea urchins in check, kelp forests can flourish. In fact, 24two years or less of sea otters can completely eliminate sea urchins in a coastal area (see chart).


Without sea otters present, 25nevertheless, kelp forests run the danger of becoming barren stretches of coastal wasteland known as urchin barrens.

[1] What was less well-known, until recently at least, was how this relationship among sea otters, sea urchins, and kelp forests might help fight global warming. [2] The amount of carbon dioxide in the atmosphere has increased 40 percent 26. [3] A recent study by two professors at the University of California, Santa Cruz, Chris Wilmers and James Estes, 27suggests, that kelp forests protected by sea otters can absorb as much as twelve times the amount of carbon dioxide from the atmosphere as those where sea urchins are allowed to 28devour the kelp. [4] Like 29their terrestrial plant cousins, kelp removes carbon dioxide from the atmosphere, turning it into sugar fuel through photosynthesis, and releases oxygen back into the air.[5] Scientists knew this but did not recognize 30how large a role they played in helping kelp forests to significantly decrease the amount of carbon dioxide in the atmosphere. [6] Far from making no difference to the ecosystem, the presence of otters was found to increase the carbon storage of kelp forests by 4.4 to 8.7 megatons annually, offsetting the amount of carbon dioxide emitted by three million to six million passenger cars each year. 31

Wilmers and Estes caution, however, that 32having more otters will not automatically solve the problem of higher levels of carbon dioxide in the air. But they suggest that the presence of otters provides a good model of how carbon can be sequestered, 33or removed; from the atmosphere through the management of animal populations. If ecologists can better understand what kinds of impacts animals might have on the environment, Wilmers contends, "there might be opportunities for win-win conservation scenarios, whereby animal species are protected or enhanced, and carbon gets sequestered."

Question 23


  • B living along the West Coast of North America, they help

  • C that live along the West Coast of North America and help to

  • D that live along the West Coast of North America, where they help

Question 24

Which choice offers an accurate interpretation of the data in the chart?


  • B even two years or less of sea otter presence can reduce the sea urchin threat

  • C kelp density increases proportionally as sea urchin density increases

  • D even after sea otters were present for ten years or more, kelp density was still lower than sea urchin density

Question 25


  • B however,

  • C hence,

  • D likewise,

Question 26

At this point, the writer is considering adding the following information.

since the start of the Industrial Revolution, resulting in a rise in global temperatures

Should the writer make this addition here?

  • A Yes, because it establishes the relationship between the level of carbon dioxide in the atmosphere and global warming.

  • B Yes, because it explains the key role sea otters, sea urchins, and kelp forests play in combating global warming.

  • C No, because it contradicts the claim made in the previous paragraph that sea otters help keep kelp forests healthy.

  • D No, because it mentions the Industrial Revolution, blurring the focus of the paragraph.

Question 27


  • B suggests-that

  • C suggests, "that

  • D suggests that

Question 28


  • B dispatch

  • C overindulge on

  • D dispose of

Question 29


  • B they`re

  • C its

  • D it`s

Question 30


  • B how large a role that it played

  • C how large a role sea otters played

  • D that they played such a large role

Question 31

Where is the most logical place in this paragraph to add the following sentence?

What Wilmers and Estes discovered in their study, therefore, surprised them.

  • A After sentence 1

  • B After sentence 3

  • C After sentence 4

  • D After sentence 5

Question 32


  • B increasing the otter population

  • C the otters multiplying

  • D having more otters than other locations

Question 33


  • B or removed from,

  • C or, removed from,

  • D or removed, from


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