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TOEFL Reading Passage 2 The Mediterranean’s Killer Algae
1. Today there are many invasive species threatening ecosystems all over the world, but few are of as much concern as Caulerpa taxifolia.This species of green algae grows in long, thin blades similar in appearance to sea grass. Each individual alga is single-celled, with a length of up to a meter, they are some of the largest cells in the world. Algae contain chlorophyll and produce their own food through photosynthesis. Also they reproduce asexually, meaning that if an alga is cut in two each half wilt develop into a whole new organism.
2. Caulerpa taxifolia’s native habitats are the tropical waters of the Caribbean, south Pacific, east Atlantic, and Indian Ocean. However, in the 1970s, a new strain was bred in Europe to decorate exhibits in saltwater aquariums. The strain proved useful for this purpose, for it was able to grow more quickly,
A. It was not known to scientists.
B. It did not flourish in a wide range of temperatures.
C. It was used primarily in freshwater aquarium exhibits.
D. It was found only off the coast of France.
