Prep Test2- essay4

[kaijen]

Test2-Essay #4. 156 (21764-!-item-!-188;#058&00156-00)

Solar ponds are bodies of water in which circulation is incomplete and there is a very high salt concentration that increases with depth. This vertical change in salinity serves to trap heat because concentrated brine in the lowest water level acts as a collector and storage area for solar heat, while the less saline, lighter water at the upper levels provides insulation. Heat is thus retained in the depths.

An artificial pond of this type has been constructed on the western shore of the Dead Sea in Israel in order to test its suitability as a source of low-grade heat for conversion into electricity. An immediate threat to the success of the venture was the growth of algae. Water in solar ponds must be kept maximally transparent to allow penetration of light to the deep storage area. Therefore, any particles of matter in the water, such as algae cells, that scatter or absorb light will interfere with the collection of heat.

One proposed method of controlling the algae was the application of an algicide. However, the Dead Sea is a closed body of water without any outlet and as such is very easily contaminated. Extensive use of chemicals in numerous future full-scale solar ponds would lead to such contamination of the Dead Sea, which now enjoys a lucrative tourist trade.

A recent experiment has supplied a more promising method for controlling the algae. To repress the algae cells' capacity for accommodating themselves to environmental changes, the water in the solar pond was first made more saline through evaporation and then diluted by a rapid inflow of fresh water. This shock reduced the cells' ability to regulate the movement of water through their membranes. They rapidly absorbed water, resulting in distortions of shape, increase in volume, and impairment to motility. Their buoyancy adversely affected, the cells sank to the bottom of the pond, where they encountered the hot waters of the storage layer and were destroyed. This method allows for effective control of nuisance algae while leaving solar ponds as one of the cleanest technologies providing energy for human use.

19. Question #12. 156-01 (21810-!-item-!-188;#058&000156-01)

The primary purpose of the passage is to

(A) discuss ways of solving a problem that threatens to limit the usefulness of an energy source
(B) explain the mechanisms by which solar heat may be converted into energy
(C) detail the processes by which algae cells colonize highly saline bodies of water
(D) report the results of an experiment designed to clean contaminated bodies of water
(E) describe the unique properties of a solar pond on the edge of the Dead Sea

Ans:(A)

Question #13. 156-02 (21856-!-item-!-188;#058&000156-02)

It can be inferred from the passage that which of the following is true about the salinity and temperatures of the highest and lowest water layers in a typical solar pond?

(A) The bottom layer is both highly saline and quite hot, while the top layer is less saline and cooler.
(B) The two layers have similar salinity levels, but the bottom layer is hotter than the top.
(C) There is no way to predict the salinity and temperature of the different water layers in different solar ponds.
(D) The bottom layer is less saline and quite hot, while the top layer is more saline and cooler.
(E) The top layer has both higher salinity and higher temperatures than the bottom layer.

Ans:(A)

Question #14. 156-05 (21902-!-item-!-188;#058&000156-05)

According to the passage, the growth of algae was considered a threat to the success of the artificial pond near the Dead Sea because the algae

(A) produce excess oxygen that lowers the water temperature in the pond
(B) restrict the circulation of water within the pond
(C) enable heat to escape through the upper level of the pond
(D) prevent light from penetrating to the lowest levels of the pond
(E) prevent accurate measurement of the heat collected in the pond

Ans:(D)

Question #15. 156-08 (21948-!-item-!-188;#058&000156-08)

Which of the following, if true, would seriously undermine the validity of the conclusions drawn from the experiment described in the last paragraph of the passage?

(A) The algae cells that sank to the bottom of the pond were destroyed only after a time lag of twenty-four hours.
(B) The lateral motility of the algae cells that sank to the bottom of the pond was not impaired.
(C) The water with which the artificial solar pond was diluted contained microorganisms that kill algae.
(D) The algae cells that sank to the bottom of the pond were actually killed by the rapid change in pressure.
(E) The higher salinity brought about through evaporation increased the transparency of the upper levels of water in the pond.

Ans:(C)

[kaijen]

Question #15. 156-08 (21948-!-item-!-188;#058&000156-08)

Which of the following, if true, would seriously undermine the validity of the conclusions drawn from the experiment described in the last paragraph of the passage?

(A) The algae cells that sank to the bottom of the pond were destroyed only after a time lag of twenty-four hours.
(B) The lateral motility of the algae cells that sank to the bottom of the pond was not impaired.
(C) The water with which the artificial solar pond was diluted contained microorganisms that kill algae.
(D) The algae cells that sank to the bottom of the pond were actually killed by the rapid change in pressure.
(E) The higher salinity brought about through evaporation increased the transparency of the upper levels of water in the pond.

Ans:(C)

請問(C)是如何weaken的呢?
我自己想了兩個解釋 可是都覺得怪怪的

1.其實algae是被微生物殺死的 否定文中掉落至storage layer而被毀滅 算是利用他因weaken
但是如果這個解釋成立的話 那(D)也算是他因否定 因為(D)說algae其實是因壓力變化劇烈而死

2.algae是被微生物殺死 但因為有微生物的存在 solar pond is contaminated
因此這個想法是建立在否定"效用"上

不知道是哪個解法才是對的? 也許有大大能夠提供其他想法..

[dibert8]

Q15 選項的判斷,可以從比較第三段與第四段著手: algae 不是外力殺死的 (e.g. 被毒死),而是自己無法反應快速的環境變化而死.所以"被外力殺死"成為弱化的最佳選項.

[Austing]

Question #15. 156-08 (21948-!-item-!-188;#058&000156-08)

Which of the following, if true, would seriously undermine the validity of the conclusions drawn from the experiment described in the last paragraph of the passage?

(A) The algae cells that sank to the bottom of the pond were destroyed only after a time lag of twenty-four hours.
(B) The lateral motility of the algae cells that sank to the bottom of the pond was not impaired.
(C) The water with which the artificial solar pond was diluted contained microorganisms that kill algae.
(D) The algae cells that sank to the bottom of the pond were actually killed by the rapid change in pressure.
(E) The higher salinity brought about through evaporation increased the transparency of the upper levels of water in the pond.

Ans:(C)

請問(C)是如何weaken的呢?
我自己想了兩個解釋 可是都覺得怪怪的

1.其實algae是被微生物殺死的 否定文中掉落至storage layer而被毀滅 算是利用他因weaken
但是如果這個解釋成立的話 那(D)也算是他因否定 因為(D)說algae其實是因壓力變化劇烈而死

2.algae是被微生物殺死 但因為有微生物的存在 solar pond is contaminated
因此這個想法是建立在否定"效用"上

不知道是哪個解法才是對的? 也許有大大能夠提供其他想法..

----
哇!呆伯特大大真的是一語驚醒夢中人!
但是我認為就看最後一段就好耶 然後去定位
然後
A--a time lag of twenty-four hours
B--lateral motility
E-- transparency
==>文中都未討論
剩
C--(我承認看到microorganisms就很想把這選項殺掉) 但其實這有提到
:因為環境中其他因素(neither distortions of shape, increase in volume, and impairment to motility, the buoyancy) 使algae死亡

D--Their buoyancy(浮力) adversely affected, the cells sank to the bottom of the pond
只是要想到浮力跟壓力是一體兩面的

[iambear2320]

M.....我看不太懂前兩位的討論@@

我自己的看法是the conclusions=This method allows for effective control of nuisance algae while leaving solar ponds as one of "the cleanest" technologies providing energy for human use. < 用的是最高級喔, 語氣很強烈>

(C)The water contained microorganisms that kill algae. -->顯然這水蠻毒的, 即使這個方式真的很有效控制algae,但是與他的結論是"the cleanest"..似乎是大大地違背了

[Huang Hsin-Yi]

支持iambear2320大的看法

[aqboy[origen]]

(B) The lateral motility of the algae cells that sank to the bottom of the pond was not impaired.

請問一下B選項為甚麼不行啊？？

They rapidly absorbed water, resulting in distortions of shape, increase in volume, and impairment to motility

可以用這句話來否定吧？

[Huang Hsin-Yi]

因為選項B並無針對題目問的結論做討論

Which of the following, if true, would seriously undermine the validity of the conclusions drawn from the experiment described in the last paragraph of the passage?

Last paragraph
This method allows for effective control of nuisance algae while leaving solar ponds as one of the cleanest technologies providing energy for human use.

(B) The lateral motility of the algae cells that sank to the bottom of the pond was not impaired. 這是weaken這個方法沒效
(C) The water with which the artificial solar pond was diluted contained microorganisms that kill algae.

Ans:(C)

[johnnywoods]

Their buoyancy adversely affected, the cells sank to the bottom of the pond, where they encountered the hot waters of the storage layer and were destroyed.
我看不懂這句子的結構，誰一位好心人可以幫我分析一下。謝謝

[Huang Hsin-Yi]

他們的浮力不利地受了影響,the cell 沉落在池塘的底部,那個它們遇到儲存區的熱水及被摧毀的地方

[johnnywoods]

謝謝你中文解釋。這裡我還有一個問題。這個句子為什麼沒有連接詞，是不是省略連接詞做分詞構句呢?