外研版 (2019)选择性必修 第一册Unit 6 Nurturing nature巩固练习

这是一份外研版 (2019)选择性必修 第一册Unit 6 Nurturing nature巩固练习，共3页。

Mathematical mdels have als revealed that fd webs may be unstable, where small changes f tp predatrs can lead t big effects thrughut entire ecsystems. In the 1960s, scientists prpsed that predatrs at the tp f a fd web had a surprising amunt f cntrl ver the size f ppulatins f ther species--including species they did nt directly attack.
And unplanned human activities have prved the idea f tp-dwn cntrl by tp predatrs t be true. In the cean, we fished fr tp predatrs such as cd n an industrial scale, while n land, we killed ff large predatrs such as wlves. These actins have greatly affected the eclgical balance.
Scientists have built an early-warning system based n mathematical mdels. Ideally, the system wuld tell us when t adapt human activities that are pushing an ecsystem tward a breakdwn r wuld even allw us t pull an ecsystem back frm the brderline. Preventin is key, scientists say, because nce ecsystems pass their tipping pint（临界点），it is remarkably difficult fr them t return.
1.What have scientists discvered with the help f mathematical mdels f fd webs?
A. The living habits f species in fd webs.
B. The rules gverning fd webs f the ecsystems.
C. The appraches t studying the species in the ecsystems.
D. The differences between weak and strng links in fd webs.
2.A strng link is fund between tw species when a predatr ________.
A. has a wide fd chice
B. can easily find new prey
C. sticks t ne prey species
D. can quickly mve t anther place
3.What will happen if the ppulatins f tp predatrs in a fd web greatly decline?
A. The prey species they directly attack will die ut.
B. The species they indirectly attack will turn int tp predatrs.
C. The living envirnment f ther species will remain unchanged.
D. The ppulatins f ther species will experience unexpected changes.
4.What cnclusin can be drawn frm the examples in paragraph 4?
A. Uncntrlled human activities greatly upset ecsystems.
B. Rapid ecnmic develpment threatens animal habitats.
C. Species f cmmercial value dminate ther species.
D. Industrial activities help keep fd webs stable.
5.Hw des an early-warning system help us maintain the eclgical balance?
A. By getting illegal practices under cntrl.
B. By stpping us frm killing large predatrs.
C. By bringing the brken-dwn ecsystems back t nrmal.
D. By signaling the urgent need fr taking preventive actin.
【语篇导读】本文讲述的是科学家们利用食物网的数学建模了解到食物网的关系，以及顶端捕食动物数量变化对其他物种的影响，进而指出人类无计划的活动会给生态系统带来极大破坏，呼吁人类采取预防措施，维持生态系统的平衡。
1. B细节理解题。根据第二段第一句With such mdels, scientists have fund ut sme key principles perating in fd webs.可知，科学家们发现了食物网运作的关键原则，此处的such mdels指的就是上文提到mathematical mdels.
【微技能】运用寻读法解细节理解题
做细节理解题一般采用寻读法，即先读题，然后带着问题快速阅读文章，找出与问题有关的词语或句子，再对相关部分进行分析对比，找出答案。另外在题干中寻找线索词，并注意题干中的名词、动词、形容词等实词。注意线索词在文章中的位置，并标出实词的出处。
2. C细节理解题。根据第二段中的When a predatr always eats huge numbers f a single prey, the tw species are strngly linked可知，当一种掠食动物总是大量猎食单一的猎物时，这两个物种间会有紧密的联系。
3. D细节理解题。第三段中讲到，顶端捕食动物微小的变化会给整个生态系统带来巨大的影响，并以20世纪60年代科学家提出的观点为例加以说明。根据第三段中的predatrs at the tp f a fd web had a surprising amunt f cntrl ver the size f ppulatins f ther species--including species they did nt directly attack可知，顶端捕食动物的数量变化极大地影响了其他物种的数量变化。
4. A推理判断题。根据第四段最后一句These actins have greatly affected the eclgical balance.可推断，第四段中所举的例子说明人类无计划的活动极大地破坏了生态平衡。
5. D细节理解题。根据最后一段中的the system wuld tell us when t adapt human activities以及Preventin is key可知，该系统会提醒我们什么时候调整人类活动，使其不让生态系统崩溃，即会通过发出需要采取预防行动的紧急信号来帮助我们维持生态系统的平衡。