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
专升本
The "balance of nature" is not an empty phrase. Nature provides a population to occupy a suitable environment and cuts down surp
The "balance of nature" is not an empty phrase. Nature provides a population to occupy a suitable environment and cuts down surp
admin
2015-10-30
19
问题
The "balance of nature" is not an empty phrase.
Nature provides a population to occupy a suitable environment and cuts down surplus population to fit the available food supply.
One means of reducing surplus population is predators(食肉动物); others are parasites(寄生虫)and diseases. Also, population density produces nervous disorders and even drives animals to mass migrations, like the lemmings(旅鼠)of Norway who plunge into(跳入)the sea.
That predators populations increase to control other animals has long been known. Many years ago, the Hudson’ s Bay Company records revealed that the fox population went up and down about a year after the rabbit population had gone up and down.
Sometimes a situation occurs in which the predators population is reduced to a level below that which nature can readily replace. On Valcour Island in Lake Champlain(New York), a costly campaign resulted in the elimination of predatory animals only to have birds and small animals—including grouse(松鸡)and hares, popular game(猎物)—increase for four years afterward. Then lacking predator control, nature resorted to diseases to cut down these populations.
Jamaica had an example of nature’ s persistence in providing animals for existing habits. Sugar planters, about 75 years ago, imported mongooses to control rats. The mongooses killed off the rats and, with plentiful food, multiplied. Rats became scarce and the mongooses ate lambs, kids, puppies(小狗), and wildlife. Eventually, food became scarce and the mongoose’s population declined.
According to the article, the phrase "balance of nature" means______.
选项
A、the relation of wildlife to man
B、the adequacy of the food supply to support its animal population
C、the ratio of small game to predators
D、the destruction of predators
答案
B
解析
the balance of nature的意思在文中第一段第二句便作了解释:Nature provides apopulation to occupy a suitable environment andcuts down surplus population to fit the availablefood supply.故B正确。
转载请注明原文地址:https://kaotiyun.com/show/ayYC777K
本试题收录于:
英语题库成考专升本分类
0
英语
成考专升本
相关试题推荐
Infact,therewashardlyanyactivityorsocialeventthatcouldnotbesettoMusic.Weddings,births,christening,funerals,
Infact,therewashardlyanyactivityorsocialeventthatcouldnotbesettoMusic.Weddings,births,christening,funerals,
Woodsmen,huntersandtrackerslearnedtofollowandreadthe【21】left,behind【22】animals,men,natureandtime.Theirabilityto
Woodsmen,huntersandtrackerslearnedtofollowandreadthe【21】left,behind【22】animals,men,natureandtime.Theirabilityto
Forthispart,youaresupposedtowriteane-mailinEnglishin100-120wordsbasedonthefollowingsituation.Remembertowri
Mancangoonincreasinghisnumbersatthepresentrate.Inthenext30yearsmanwillfaceaperiodofcrisis.Someexpertsbe
ThehomecomputerindustryhasbeengrowingrapidlyintheUnitedStatesinthelasttenyears.Computersusedtobelarge,expe
Likealllargecities,NewYorkhasoldproblemstosolveand【21】onestoface.Slums(贫民窟)mustbecleared,andnewhousingconst
Likealllargecities,NewYorkhasoldproblemstosolveand【21】onestoface.Slums(贫民窟)mustbecleared,andnewhousingconst
随机试题
下列选项中,属于现代社会个人品德修养的正确途径是
市场体系可简单划分为________和________。其中,商品市场包括________和________;生产要素巿场既包括________、________、________、________、________,也包括________。
“不积跬步,无以至千里;不积小流,无以成江海。”这说明()
能说明有机磷中毒及其程度的检验是
具有温和和熟腐功能的是能为万物运动和生长提供空间的是
HYFA—400×2×0.5型号电缆的读法是()。
计算机最主要的功能是处理信息,如处理数值、文字、声音、图形和图像等。()
MBA是一种高级企业管理人才,对MBA来说最重要的一点在于企业家精神,具有企业家精神的MBA是市场中的佼佼者。我国现在招收MBA的院校有50多所,有很多还宣称与国外院校合办,但大多是一些三流院校,有的连正式的教材都没有,其良莠不齐可见一斑。由此可推知(
下列属于毛泽东和邓子恢等一起制定土地革命中阶级路线和土地分配方法的是()
设φ(x)=,求φ’(x),其中a>0,b>0.
最新回复
(
0
)