高考英语阅读理解精英系列练习题（20）.doc

2014 高考英语阅读理解精英系列练****题( 20 )及答案【广东省广州市 2013 综合测试( 2)】D Expensive perfumes ( 香水) come in tiny bottles, but many hide a whale-sized secret. To perfect a particular smell, perfume-makers often use an ingredient es from sperm whales, called ambergris. But using ambergris, which helps a perfume last longer, is strongly opposed by many people who think it is wrong to kill whales just so we can smell sweet. Joerg Bohlmann is neither a perfumer nor a whale expert. He's a plant biologist at the University of British Columbia in Canada. But his discovery ofa new plant gene ( 基因) might push whales out of the perfume business. The es from fir trees, found throughout North America monly used as Christmas trees. The trees produce a chemical that can be used in perfume in place of ambergris —— but with a catch . "There's a problem that many people wouldn't consider. In the tree, the chemical is mixed with many others. That makes separation a challenge," Bohlmann says. "It's like trying to isolate sugar from a biscuit." This is where science es useful. When Bohlmann learned that fir trees produce the ambergris-like chemical, he decided to use his gene know-how to find the instructions for how to make the ambergris-substitute. Bohlmann found that gene and took it out of the tree cells. Then he did something that might sound strange to someone who doesn't work in ics: Bohlmann put the gene from th