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
A、A community of plants. B、A community of animals. C、The study and understanding of plants and animals. D、The interacting physic
A、A community of plants. B、A community of animals. C、The study and understanding of plants and animals. D、The interacting physic
admin
2013-06-02
39
问题
No living creature, plant or animal, can exist in complete isolation. An animal is bound to depend on other living creatures, ultimately plants, for its food supply; it must also depend upon the activities of plants for a continued oxygen supply for its respiration. Apart from these two basic relationships, it may be affected directly or indirectly in countless different ways by other plants and animals around it. Other animals prey on it or compete with it for the same food; plants may provide shelter, concealment or nesting material, and so on. Similarly, the animal will produce its own effects on the surrounding plants and animals: some it may cat or destroy, for others it will provide food; and through its contribution of manure it may influence the texture and fertility of the soil.
This dependence on other living things is not confined to animals. Though plants manufacture their own food, they are dependent on animal respiration for at least a part of the carbon dioxide which they use as raw material in this process. Moreover, despite the apparently peaceful relationships in plant communities, there is intense competition going on for water, nutrient salts, and above all, for light.
The whole complex of the plants and animals forming a community, together with all the interaction physical factors of the environment, really forms a single unit, which has been called an ecosystem. It will be seen that the final aim of ecology -- the complete understanding of ecosystems -- is an ideal one we can scarcely hope to attain. It is nevertheless an ideal well worth pursuing and valuable progress has been made towards it.
选项
A、A community of plants.
B、A community of animals.
C、The study and understanding of plants and animals.
D、The interacting physical factors of the environment.
答案
C
解析
转载请注明原文地址:https://jikaoti.com/ti/Qm5FFFFM
0
大学英语六级
相关试题推荐
TelevisionhastransformedpoliticsintheUnitedStatesbychangingthewayinwhichinformationisdisseminated,byalteringp
A、Acomparisonoffishasacold-bloodedanimalwithwarm-bloodedanimals.B、Thedifferencebetweenwateranimalsandlandanima
CreaturesoftheThermal(热量的)VentsThethree-personsubmersibleAlvinsankthroughthecold,darkwatersofthePacificOc
CreaturesoftheThermal(热量的)VentsThethree-personsubmersibleAlvinsankthroughthecold,darkwatersofthePacificOc
A、Howtobecomeadoctor.B、Howtogetintoamedicalschool.C、Theexpenseforstudyinginmedicalschools.D、Studyprogramsin
A、Helosthismother.B、HewasunhappyinCalifornia.C、Hemissedhisaunt.D、Hehadtoattendschoolthere.A细节题。文章中男士提到Hewasn
A、Thelocationofthesessionhasbeenchanged.B、Shewilldefinitelygotothesessionthisevening.C、She’llprobablybetoot
Itisacommonplaceamongmoraliststhatyoucannotgethappinessbypursuingit.Thisisonlytrueifyoupursueit【62】.Gamble
DaphnaEdwardsZimanisoneofthefamousmothersinAmericanhistory.Sheisthemotherofan(36)______child,forWhomsheha
A、Suegotpromoted.B、Johnhadtoquithisjob.C、BothJohnandSuegotaraise.D、Suefailedtocompleteherproject.A录音结尾提到,
随机试题
“注意分寸”“掌握火候”“适可而止”等说法,都是要求在实践中坚持()
企业、事业单位之间联营,按照合同的约定各自独立经营的,它的权利和义务由合同约定,共同承担民事责任。
下列对胸内压的叙述,哪一项是错误的
将预算定额划分为建筑工程定额和安装工程定额两类,其划分标准是()。
当一个集团客户授信需求超过一家银行资本余额的15%以上时,应采取风险分散措施。()
甲、乙、丙、丁合谋,集中资金优势、持股优势或者利用信息优势联合买卖或者连续买卖证券,影响证券交易价格,从中牟取利益的行为是欺诈客户行为。()
()是在分音列的第二分音和第三分音之间再插入第五分音,构成大三和弦形式来作为生律要素。
古人有时不直接说出某人多少岁或自己多少岁,而是用一种与年龄有关的称谓来代替。下各称谓,按年龄从小到大的顺序排列正确的是()。
美国项目管理协会(PMI)于2003年公布了组织级项目管理成熟度模型(OPM3),OPM3的最佳实践由过程组、知识领域和过程改进的若干个阶段组成。其中过程改进的四个阶段是(39)。
TheUSvetoedaUNSecurityCouncilresolutioncallingongovernmentstoobserveinternationallaw.Afterdeliberatelytargeting
最新回复
(
0
)