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
Coral reefs are one of the most fragile, biologically complex, and diverse marine ecosystem on Earth. This ecosystem is one of t
Coral reefs are one of the most fragile, biologically complex, and diverse marine ecosystem on Earth. This ecosystem is one of t
admin
2014-09-18
93
问题
Coral reefs are one of the most fragile, biologically complex, and diverse marine ecosystem on Earth. This ecosystem is one of the fascinating para- doxes of the biosphere: how do clear, and thus nutrient-poor waters support such prolific and productive communities? Part of the answer lies within the tissues of the corals themselves. Symbi- otic cells of algae known as zooxanthel-lae carry out photosynthesis using the metabolic wastes of the coral thereby producing food tor themselves, for their corals, hosts, and even for other mem- bers of the reef community. This symbiotic process allows organisms in the reef community to use sparse nutrient resources efficiently.
Unfortunately for coral reefs, how- ever, a variety of human activities are causing worldwide degradation of shallow marine habitats by adding nutrients to the water. Agriculture, slash-and-burn land clearing, sewage disposal and manufacturing that creates waste byproducts all increase nutrient loads in these waters. Typical symptoms of reef decline are destabilized herbivore populations and an increasing abundance of algae and filter-feeding animals. Declines in reef communities are consistent with observations that nutrient input is increasing in direct proportion to growing human populations, thereby threat- ening reef communities sensitive to subtle changes in nutrient input to their waters.
It can be inferred from the passage that the author describes coral reef communities as paradoxical most likely for which of the following reasons?
选项
A、They are thriving even though human activities have depleted the nutrients in their environment.
B、They are able to survive in spite of an over-abundance of algae inhabiting their waters.
C、They are able to survive in an environment with limited food resources.
D、Their metabolic wastes contribute to the degradation of the waters that they inhabit.
E、They are declining even when the water surrounding them remains clear.
答案
C
解析
作者为什么说珊瑚礁群落“看似矛盾”?文中L6—8明确指出:贫营养水体支撑大量生物种群。∴C正确,能在食物有限的环境下生存。A、B、D、E皆不合原文叙述。
转载请注明原文地址:https://kaotiyun.com/show/4gtO777K
本试题收录于:
GMAT VERBAL题库GMAT分类
0
GMAT VERBAL
GMAT
相关试题推荐
Normallyastudentmustattendanumberofcoursesinordertograduate,andeachcoursewhichheattendsgiveshimagradewhic
Thereisnothing______aboutanativeEnglish-speakingteacherexceptthathespeaksEnglisheasilyandwell.
JardenZinc(锌)Products,alargezincplantafewmilesoutsideGreeneville,Tennessee,hasaspecialclaim.Since1982,ithas
JardenZinc(锌)Products,alargezincplantafewmilesoutsideGreeneville,Tennessee,hasaspecialclaim.Since1982,ithas
Ioncefoundoutthatdoingafavorforsomeonecouldgetyouintotrouble.Iwasintheeighthgradeat【C1】______time,andwew
Withthepossibleexceptionofequalrights,perhapsthemostcontroversialissueacrosstheUnitedStatestodayisthedeathpe
Whenproductsmadeinfactories______,theyarethrownawayasgarbage.
Therestthatyougetwhilesleepingenablesyourbodytoprepareitselfforthenextday.
Pleaseturntheradio________.Thebabyissleeping.
Bigdatacanbedefinedasinformationthatistoobigorcomplextobecontainedorprocessedbyanyonemachineorperson.
随机试题
以下关于SQL视图的描述中,正确的是________。
完全禁食数日,蛋白质分解主要来自()
哪项不是急性盆腔炎的后遗症()
背景资料:陈村拦河闸设计过闸流量2000m3/s,河道两岸堤防级别为1级,在拦河闸工程建设中发生如下事件:事件一:招标人对主体工程施工标进行公开招标,招标人拟定的招标公告中有:①投标人须具备堤防工程专业承包一级资质,信誉佳,财务状况良好,类似工程经验
Gary,agray-hairedman,isclimbinguptooldOakHillCemetery.Henoticesatombwithanationalflagonitraiseshisbugle
下列有关法学的表述.正确的是()。
1927年,北京《顺天日报》评选“首届京剧旦角最佳演员”,其中被评为“四大旦角”的是:
设f(x)在[0,1]上连续,f(0)=0,∫01f(x)dx=0.证明:存在ξ∈(0,1),使得∫0ξ(x)dx=ξf(ξ).
Writeanessayof160-200wordsbasedonthefollowingdrawing.Inyouressay,youshould1.describethedrawingbriefly,
下列关于计算机图形图像的描述中,不正确的是______。
最新回复
(
0
)