首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
In their world of darkness, it would seem likely that some of the animals might have become blind, as has happened to some cave
In their world of darkness, it would seem likely that some of the animals might have become blind, as has happened to some cave
admin
2011-01-26
41
问题
In their world of darkness, it would seem likely that some of the animals might have become blind, as has happened to some cave fauna. So, indeed, many of them have, compensating for the lack of eyes with marvelously developed feelers and long, slender fins and processes with which they grope their way, like so many blind men with canes, their whole knowledge of friends, enemies, or food coming to them through the sense of touch.
The last traces of plant life are left behind in the thin upper layer of water for no plant can live below about 600 feet even in very clear water, and few find enough sunlight for their food-manufacturing activities below 200 feet. Since no animal can make its own food, the creatures of the deeper waters live a strange, almost parasitic existence of utter dependence on the upper layers. These hungry carnivores prey fiercely and relentlessly upon each other, yet the whole community is ultimately dependent upon the slow rain of descending food particles from above. The components of this never-ending rain are the dead and dying plants and animals from the surface, or from one of the intermediate layers. For each of the horizontal zones or communities of the sea that lie between the surface and the sea bottom, the food supply is different and in general poorer than for the layer above.
Pressure, darkness, and silence are the conditions of life in the deep sea. But we know now that the conception of the sea as a silent place is wholly false. Wide experience with hydrophones and other listening devices for the detection of submarines has proved that, around the shore lines of much of the world, there is the extraordinary uproar produced by fishes, shrimps, porpoises and probably other forms not yet identified. There has been little investigation as yet of sound in the deep, offshore areas, but when the crew of the Atlantis lowered a hydrophone into deep water off Bermuda, they recorded strange mewing sounds, shrieks, and ghostly moans, the sources of which have not been traced. But fish of shallower zones have been captured and confined in aquaria, where their voices have been recorded for comparison with sounds heard at sea, and in many cases satisfactory identification can be made.
During the Second World War the hydrophone network set up by the United States Navy to protect the entrance to Chesapeake Bay was temporarily made useless when, in the spring of 1942, the speakers at the surface began to give forth, every evening, a sound described as being like "a pneumatic drill tearing up pavement". The extraneous noises that came over the hydrophones completely masked the sounds of the passage of ships. Eventually it was discovered that the sounds were the voices of fish known as croakers, which in the spring move into Chesapeake Bay from the offshore wintering grounds. As soon as the noise had been identified and analyzed, it was possible to screen it out with an electric filter, so that once more only the sounds of ships came thorugh the speakers.
Which of the following statements about the state of oceanographic research does the text most clearly support?
选项
A、Undersea research is still incomplete.
B、Technology used in undersea studies is still in a very primitive stage of development.
C、More undersea research is conducted near shore than in mid ocean.
D、Military researchers have made several momentous discoveries about undersea life.
答案
C
解析
海滨附近进行的海底研究比海洋当中的海底研究要多。第三段中有一句话说,到目前为止,在离海滨很远的深水区,人们很少研究海中发出的声音,这句话暗示,在离海滨很近的地方,人们所作的海底研究较多。
转载请注明原文地址:https://kaotiyun.com/show/qFBO777K
0
考博英语
相关试题推荐
Lookatthenotesbelow.Someinformationismissing.Youwillhearadialogueonanewproject.Foreachquestion(9-15),filli
Lookatthenotesbelow.Someinformationismissing.Youwillhearadialogueonanewproject.Foreachquestion(9-15),filli
Lookatthenotesbelow.Someinformationismissing.Youwillhearapresentationonanewproject.Foreachquestion(16-22),f
TheNationalFoodCouncilhasstudied______.
CONTINENTAIRLINEFlightReservationFormDESTINATION:【A1】______CONTACTNAME:【A2】______FLIGHTNUMBER:【
Youplantoattendaninternationaladvertisementexhibition,andyouwanttofindapromisingadvertisementagencytoberespon
Youhaveorderedsomenewofficeequipment.However,someofthisequipmentwillarriveaweeklaterthanplanned.Writeamemo
Thenumberofvehiclesleasedremainedlowthroughouttheyear,risingonlybrieflyabovesales,whichfluctuateddramaticallyi
Lookatthegraphsbelow.Theyshowunemploymentineightdifferentregionscomparedtothenationalaverage.Whichregiond
Whetheryouwantaccesstoalltheday’snewsfast,breakinganalysisoftheevents,aconsideredviewoftrends,expertcomment
随机试题
测定原油含砂时,用搪瓷量杯取鲜油样()并充分搅拌,使原油彻底脱气。
下列项目计征全年个人所得税时,允许从收入中直接减除费用6万元计算应纳税所得额的有()
除下列哪项外,均是采用观察法收集的资料
钢筋混凝土梁正截面可能出现()不同性质的破坏。
按照我国建筑法的规定,施工现场安全由( )负责。
外商投资的有限责任公司的股东首次出资额应当符合法律、行政法规的规定,其余部分应当自公司成立之日起( )内缴足,其中,投资公司可以在( )内缴足。
市净率越高,说明股票的投资价值越高,股价的支撑越有保证。( )
大多数价格高的毛衣质量较好,少数价格低的毛衣质量也好。所有质量好的毛衣穿起来都很舒适。根据上述命题,可以推出的是()。
2000年9月,天泉市政府为周某办理了地处水湾村某地块的《集体土地建设用地使用证》(以下简称《土地使用证》),水湾村委会不服,向天泉市法院提起行政诉讼,要求撤销天泉市政府为周某所颁发的《土地使用证》。原告诉称,周某系城镇非农业户口。周某没有向水湾村提出宅基
下列属于合法的Java标识符是
最新回复
(
0
)