TOEFL Sample Question
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CLI 아카데미
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2013-06-29 10:53
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Read the following passage. Then fill in the diagram with the information that you read.
Phragmites Austalis
An invasive species is a non-native plant or animal that adversely affects the habitat in which it lives. The invasive species can bring about economical, enviromental, or ecological effects. Some invasive species lack predators (animals that would kill and eat them) and multiply rapidly. This lack predation allows them to devastate other plant or animal populations, and exxentially overwhelm an environment. Other may have an internal advantage. The Phramites australis plant (also known as the common reed) is an invasive plant of the latter type. It uses a very strong chemical substance to poison competing plants.
Phragmites plants damage other plants by secreting an acidic substance called gallic acid. Gallic acid is a chemical. The toxin attacks and destroys the proteins of the roots of other species. This causes them to collapse from within due to structural intability. Thus, the Phragmites becomes dominant by removing the competition from its surroundings. Other plants also use allelopathy in their defense against other plants. However, the Pharagmites is unque because it uses its poison to invade and conquer ecosystems, rather than merely to defend its habitat.
The Phragmites has many effects upon incaded ecosystems. First, they are reducing biodiversity by destroying species native to certain areas. Even animals are affected by this invasion. As the Paragmites invades and destroys native plant species, many animals lose their primary food sources. Thus, the ecosystems in these regions may be facing an ecological catastrophe. In addition, the Phragmites australis is significantly altering geological structure. In areas most severely affected by the invasions, researchers have noticed a dramatic change in their hydraulic structure. Regions that used to be cjaracterized by open pools and an abundance of water are currently facing drier conditions. Also, they now featuer thick concentrations of Phragmites plants. This will likely harm the biodiversity of these areas. Eventually, native plant and animal species that rely upon wet conditions for survival will essentially be evicted from these regions.
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Devastate: to destroy completely
Overwhelm: to harm through excesseive numbers
Secrete: to release a fluid
Toxin: a posion
Allelopathy: a plant’s use of poison to protect itself
Biodiversity: the state of variety between plants and animal of area
Catastrophe: a disaster
Hydraulic: pertaning to moving water
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Q. What dose the author imply in paragraph 2?
(A) Allelopathy is not typically used to gain territory.
(B) The Phragmites is hazardous to humans and other animoals.
(C) The Phragmites’s competitors also secrete gallic acid.
(D) Allelopathic behavior harms the soil of an ecosystem.
A > (A) Allelopathy is not typically used to gain territory.