备考tpo42听力答案Lecture3。
Lecture3(Environmental Science)
QUESTIONS
1. What is the lecture mainly about?
A. Why fungi cannot grow well in polluted ecosystems
B. Why fungi pose a danger to the underground water system
C. How to prevent heavy metals from getting into the soil
D. How fungi can clean up pollution that is in the soil
答案：C
解析：题目考察文章主旨。全文都在讲如何防止重金属进入土地进而形成污染，lecture的结尾还在讲蘑菇可以作为有效的清洁污染的能源，因此C选项正确。
2. What does the professor say about the way fungi get their food?
A. They use certain metal compounds in the soil as nutrients.
B. The enzymes that they produce allow them to absorb organic nutrients from the soil.
C. They separate nutrients from heavy metals and then return the metals to the soil.
D. Heavy metals interfere with their way of getting nutrients from the soil.
答案：B
解析：根据原文 A fungus creates enzymes into the soil, enzymes that break down, decompose organic material in the soil, so the fungus can absorb this material and get nutrition. 可知酶可以从土中产出菌类需要的有机营养，所以B选项正确。
3. What two points does the professor make about chitin?
Click on 2 answers.
A. Chitin binds strongly to certain heavy metals.
B. Insects need chitin in order to digest the fungi they eat.
C. Chitin can be added to soil to create a good habitat for fungi.
D. The cell walls of fungi, like the exoskeletons of insects, contain chitin.
答案：A, D
解析：根据原文But beyond that, the filaments also pull out of the soil a great deal of the pollution that might be in there, especially heavy metals. 所以A选项正确。
根据原文 Believe it or not, the only other place that chitin is found abundance is in the exoskeletons of insects, crabs and such. 所以D选项正确。
4. What do adsorption and absorption in fungi have in common?
A. They both can help the production of new filaments.
B. They both can increase the production of chitin.
C. They both can help keep pollutants out of groundwater.
D. They both result in the strengthening of cell walls.
答案：C
解析：根据原文 And thereby detoxify a large soil ecosystem. The heavy metals are still there, but instead of leaching into the water system and contaminating the water underground, large amounts of these metals may remain bound to the chitin to the cell walls of filaments fungi and the soil. 可知菌类的吸附和吸收作用都可避免污染物污染地下水。所以C选项正确。
5. Why does the professor mention the antibiotic penicillin?
A. To suggest that more fungi should be investigated as potential sources of medications
B. To point out that certain heavy metals are needed for the production of penicillin
C. To criticize the pharmaceutical industry for contributing to environmental pollution
D. To show how a waste product from one process can be useful in another process
答案：D
解析：根据原文We can put these filters into waste pipes from industrial processes and use the filters to trap heavy metal like mercury and zinc. 可知这些生产出的废物其实都是可被再次利用的，因此D选项正确。
Listen again to part of the lecture. Then answer the question.
6. Why does the professor say this:
A. She does not have time to fully explain the reason.
B. She is hopeful that students will be able to figure out the reason.
C. She wonders why mushrooms are not already used for cleaning up pollution.
D. She realizes that the research she has been discussing is still in its early stages.
答案：C
解析：教授说For some reason, this hasn’t happened yet as far as I know, but I can easily envision cultivating mushrooms for the sole purpose of detoxifying a large underground ecosystem. 所以C选项正确，因为教授好奇为什么蘑菇还没有被用来清理污染物。
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