問題詳情

III. Passage Completion (12%)    Elizabeth Lopez maneuvered a massive steel claw over the side of a sailboat and guided its descent throughswaying kelp and schools of fish 10 miles off the coast and San Diego. She was hoping to catch pieces of amysterious marine ecosystem that scientists are calling the plasticsphere.    It starts with particles of __19__ plastic no bigger than grains of salt. Bacteria take up __20__ on those tinypieces of trash. Then single-celled animals feed on the bacteria, and larger __21__ feed on them. “We’ve created anew man-made ecosystem of plastic debris,” said Lopez, a graduate student at the University of San Diego.    The plasticsphere was six decades in the __22__. It’s a product of the discarded plastic – flip-flops, margarinetubes, toys, toothbrushes – that gets swept from urban sewer systems and river channels into the sea. When that debriswashes into the ocean, it breaks down into bits that are __23__ by microscopic organisms that scientists are justbeginning to understand. Researchers suspect that some of the __24__ may be pathogens hitching long-distance rideson floating junk.    Scientists also fear that creatures in the plasticsphere break down chunks of plastic so completely that dangerouschemicals __25__ into the environment. “This is an issues of great concern,” said Tracy Mincer, a marine geochemistat the Woods Hole Oceanographic Institution in Massachusetts. About 245 millions tons of plastic is producedannually around the world, according to industry estimates. That represents 7- pounds of plastic annually for each ofthe 7.1 billion people on the planet, scientists say.    The waste gathers in vast ocean “garbage patches” formed by __26__ currents and winds. Once trapped in thesedead zones, plastic particles may persist for centuries.    Edward Carpenter, a professor of microbial ecology, first reported that microbes could attach themselves toplastic particles __27__ at sea 1972. He observed that these particles enabled the growth of algae and probablybacteria and __28__ that hazardous chemicals may have leached out of bits of plastic. Carpenter’s discovery wentlargely __29__ for decades. But now scientific effort to understand how the plasticsphere influences the oceanenvironment has become a growing field of study. Scientists are collecting seawater and marine life so they cananalyze the plastic fragments they contain. Their findings are shedding new light on the __30__ of humanity’saddition to plastic.    “We’re changing the basic rhythms of life in the world’s oceans, and we need to understand the consequences ofthat,” said marine biologist Miriam Goldstein, who studied plastic debris in the Great Pacific Garbage Patch betweenHawaii and California. 
19.

參考答案

答案：B,E
難度：適中0.4
統計：A(1),B(2),C(0),D(1),E(2)

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