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GMAT考试-10月22日换题库阅读新题时时更新(29号更新)-Natural Science Division

2.1.        Biology        24
2.1.1保护动物        24
2.1.2猛兽灭绝 △        25
2.1.3  native species declines        29
2.1.4 lepidoptera★        30
2.1.5蟾蜍与青蛙★        33
2.1.6恐龙灭绝  △        34
2.1.7鸟过冬        40
2.1.8  DNA与细菌        40
2.1.9 古文物DNA        41
2.1.10  beetle 甲虫△        41
2.2.Geography & Geology        42
2.2.1中国人测量喜马拉雅山 ★        42
2.2.2 地震 △        44
2.2.3 测量误差        46
2.3.        Astronomy & Environmental Science        46
2.3.1暗物质 △★        46
2.3.2某星球北极上的冰△        51
2.3.3  clock △        53
2.3.4月亮的形成 △        55
2.3.5 小行星撞击 △★        60
2.3.6 Moon-earth 生命体        63
2.3.7 星系△        64
2.3.8 CQBIS009        66
2.3.9 云的形成        66
2.3.10 元素与光照        66
2.3.11 太阳粒子与大气变化        66
2.1.11龙卷风  tornado        67
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2.1.        Biology
2.1.1保护动物
V1  【by: arieslee0410】
第一段提出了一种方法来保护动物,具体是什么不记得了,但是没题目的,最后作者表明这种方法的使用其实是需要考虑很多其他因素的,就是很复杂的,反正我感觉是否定的意思

第二段提出了这方法的一个问题,忘了……sorry……
哦~想起来了,但是我不敢确定对不对……就是科学家们没法确定到底应该保护哪些动物,是保护那些快要灭绝的呢还是保护那些生孩子成活率低的呢(我觉得是这意思)?最后一句是个高亮句,反正是个问句,说你是要保护xxx还是yyy?无法确定~(问题就是问这句话有啥作用)

第三段提出另一个问题,说科学家们总是倾向于保护那些他们已经研究过的动物,但有些动物事实上他们也不知道到底是不是快灭绝了。因此他们risk overemphasized……(此处有题,问科学家们容易有什么风险)

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2.1.2猛兽灭绝 △       

V1  【by: 花子落落】

第一段讲非洲和什么洲的什么猛兽只有20%-30%(数字不确定)再A时期灭绝,澳大利亚和什么洲的同样大型猛兽七八十吧(数字不确定,但是比前面大很多)在B时期(比A晚很多年)灭绝。作者认为是因为在A时期猛兽有时间去适应人类逐渐变强变得可以消灭他们。而B时期,人类能力已经很强了。
第二段不太记得了,大概是继续证明上述观点吧。好像是有人说是因为是天气原因,然后作者举例两个相近的地方,如果是因为天气原因,那么这两个地方的猛兽应该都在同样的时间消失,但是事实不是这样。所以作者继续坚持自己的观点。
第三段给了两个反对作者观点的意见。第一个ms是和植物灭绝有什么关系,但是作者认为虽然和动物灭绝滴证据很少(little之类的词修饰的吧),但是整个就没有(记得作者用的是no)和植物灭绝有关的evidence。第二个是什么忘记了,作者就是又反驳了这个观点。总之,作者就是坚持自己的观点。
这篇阅读印象比较深刻。

V2  【by: BlueheartTseng】

讨论亚洲,非洲,澳洲还有m什么地方的大型动物(?)在不同时期大量灭绝的问题。第一段提出一个是人类把这些动物都给干了,但是非洲和亚洲这些动物灭绝的少一些,其他地方挺多的(这儿有个细节忘了,有题——为什么亚洲和非洲的少,我选的这儿的人养殖还是耕种什么的,忘了)二,三段又说神马人反对,说是可能由于气候原因还有什么的(题——如果是气候原因会发生什么),然后作者说如果是气候原因的话应该XX地和YY地的大型动物同时灭据,但事实上没有,反正都被作者给驳倒了。
主旨题:main purpose好像是一个theory并支持它。

V3  【by: xu_shining】

大型动物的灭绝和人类的捕猎有关,然后提出了很多论据证明这一观点。最后一点驳斥了他人的反对意见:一,大型动物灭绝是气候所致;二人类的捕猎技术不能达到比如补杀野牛得水平

V4  【by: lion1096】

第一段就是说非洲,亚洲等等人类迁移较早的地区,动物在一个较早的时期内灭绝的较少,15%左右(数据比较确定,但是不考)。。。然后澳洲、美洲等等人类取得较玩的地方在较晚的时候反而大规模灭绝80-95%左右(数字依然比较确定然后依旧不考)。然后就说这是因为亚非等等的动物AND人类一起生活,慢慢人类的进步,比如狩猎工具的进步,然后比较有时间去慢慢适应,然后那些人类较晚的因为过去很少有人而且人类更加发达,然后就大规模灭绝。(有题,文章主旨,以及作者的对这个大灭绝原因的同意)。顺便说下,那个人类较早迁徙和较晚迁徙文章中没有直接提到,但这基本是个常识,也为了同学们理解方便就顺便补上了。
第二段将有人提出可能是气候原因,然后作者反驳,说如果是气候原因那为神马美洲(还是非洲?)周围的群岛以及澳洲AND澳洲周围的新西兰的大型猛兽没有同时灭绝。。。。然后这里有题问如果是气候原因应该是怎么样?
第三段也是反驳另一种理论,但是不考,可以忽略。意思也大概说下,就是有些人说猛兽灭绝的化石证据不足,但是作者说已经很充足了,如果和植物的化石一比,意思植物化石很少很少。总之就是为了证明是人类还有猛兽的适应性等等。

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V5  【by: lTopway  750】

作者观点:猛兽灭绝跟人类有关。
第一段,讲了三个地方,第一个地方在60000年灭绝了15%,第二个地方在40000年前灭绝了80%。第三个地方blabla。然后讲原因,因为第一个地方的动物适应了人类的捕猎,而第二个地方的人类来的太快,没动物没来的及适应(问题:为什么第一个地方比第二个地方灭绝的百分比小?)
第二段:讲灭绝不会是因为气候引起的,如果是气候原因,A地和B地距离很近,但是动物灭绝时间却不一样。(问题:如果是气候引起的灭绝,会怎么样?)
第三段:又提出别人的两种观点,作者又一一反驳。第二个观点处有题,我想不起来了。。。

V6  【by: serenashu】

M灭绝那个,狗狗里面有~~就是第一段讲是人们造成的,举了一些例子~~
第二段讲是气候造成的,但是后来被否定了,因为临近几个地方的其他动物什么的都没灭绝,这里举了两个例子,都是和地理位置靠的近什么(后面的网了,看看以前的吧)
我想说文章真的很熟悉,可是题目满陌生的,但是也不是很难,我也想不起来了~~~

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考古:ryangu619(已确认)

RC-22时期M动物的灭绝
v1
第一段,一个是maya(某种动物)的灭绝是因为人类的殖民发展,它在亚洲和非洲可能会上升..和美洲想比 balabal之类(我认为作者是认同这个观点的)
 第二段,说一个反对观点是因为天气,接着举例排除了这个可能性...另一个反对观点说是因为maya没有存活技能,后来通过fossil又排除了这个观点..这个考了两个文章结构题..还有举例说作者会同意下面那一项...
  
v2
还有个阅读,讲M动物在P时代灭绝。跟JJ一样。很简单。题目基本都忘记了。但是大家都应该能把这阅读的题都作对。
问题:1.问「 If hunting evidence are small, then the collecting evidence is nonexistent.」这句话被作者拿来做什么用?
  我选「不能用来作为反驳「人类活动造成m动物灭绝」这个理论的理由」
2.问作者对第二个counterargument(即人类狩猎技术不够好)的反驳暗指下列哪件事?
  我选「更新世动物的防御能力较现存动物低」
#第二个counterargument是说古时候人类狩猎技巧不高明,所以应该很难将m动物的灭绝归因于人类。但是作者驳斥说,并不需要高超的狩猎用具(用于捕捉现在的大型动物,如大象)就可以捕捉到m动物,因为m动物的防御能力并不如现在的大象等,所以自然也不需要高超的狩猎工具。

v3
说一种大型动物的灭绝问题。三段:第一段,先说了他们分别在几个洲灭绝的时间和percent。然后结论是因为人类的捕猎。第二段,说是不是天气原因呢。举了例子说不是,如果是也会影响小动物和植物。这里有考题,说作者用什么论点推翻这个假设的。第三段,有人说化石里面没有证据,作者就说如果这个证据很少,别的更没证据。反正作者就是认准了是human hunter。讨论了为什么在亚洲和非洲减少的比较慢,早期时候,我答的是因为那时候人类发展慢,动物有时间适应,美洲都是直接拿枪去殖民的。第一段有,可以确认下。

V4
第二篇是说大型动物M(貌似是猛犸象吧~)的灭绝原因,基本上作者就是先描述一下灭绝的时间和情况然后说不知道是人类原因还是气候原因,中间是排除气候原因,然后说就是人类HUNTING造成的。也不难。有一个题目说解释一个曾经发生的“lighter extinction”,文中说的是当时人们也处于捕猎技术成长的阶段,那些动物就有时间去适应,答案就是这个意思的一个改写
  
V5
史前(P开头的那个单词)大动物(M开头单词)灭绝理论 Quaternary extinction event
  (1)P时期大动物灭绝很快,最早在亚非,接着到澳洲和美洲(都有具体年份说明的,比如15000年前),好奇怪。为什么呢?学者A说是因为人类活动。因为这些时间都对应着相应地区的人类频繁活动。为了进一步说明,A还说一:灭绝的都是那种又大又笨的,容易被人抓到,二:亚非的大动物灭绝的不如澳美的 drastically,是因为人类是突然到澳美洲的,大动物都来不及反应。(有题问道亚非动物灭绝的为什么比澳美缓慢)
  (2)顺承上文,继续支持A(没有问道问题,没记得很多)不过有说道,历史上如果由CLIMATE造成的物种灭绝都是更大范围,而且大物种,小物种一起灭绝的,但这个P时段的灭绝只涉及大物种,所以还是认为还是人类干涉而不是气候。
  (3)但是这个解释又两个counterargument,(但最后还是被作者反对掉了,说明作者是支持A的)counterargument一:根据fossil,P时代人类主要靠collect植物什么的过活,化石没有反映出人类hunting,作者反对,提出一句话:if hunting evidences are "small", then the collecting evidence are nonexistent. (这句话有考题,但有点忘了);counterargument二:在那个时代人类捕猎水平不够,根本不可能造成那么多物种灭绝,说道要用rifle之类的才能造成,另外还说到,大动物如果被捕猎死的话,死相会有挣扎的痕迹,但是没有。最后作者还是把这个反对了下(没仔细看了)。720 (M50 V37)

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  相关文章, 背景知识
  Pleistocene megafauna 更新世动物
  In broad usage, the Holocene extinction event includes the notable disappearance of large mammals, known as megafauna, by the end of the last glacial period 9,000 to 13,000 years ago. Such disappearances have been considered as either a response to climate change, a result of the proliferation of modern humans, or both. These extinctions, occurring near the Pleistocene–Holocene boundary, are sometimes referred to as the Quaternary extinction event or Ice Age extinction event. However the Holocene extinction event continues through the events of the past several millennia and includes the present time.
  These species appear to have died off as humans expanded out of Africa and Eurasia, the only continents that still retain a diversity of megafauna comparable to what was lost. Three theories have been given for these extinctions: hunting by the spreading humans, climatic change, and spreading disease. A combination of those explanations is also possible.
  Human Hunting
  This hypothesis was proposed 40 years ago by Paul S. Martin。This theory holds Pleistocene humans responsible for the megafaunal extinction. One variant, often referred to as overkill, portrays humans as hunting the megafauna to extinction within a relatively short period of time. Some of the direct evidence for this includes: fossils of megafauna found in conjunction with human remains, embedded arrows and tool cut marks found in megafaunal bones, and cave paintings that depict such hunting. Biogeographical evidence is also suggestive; the areas of the world where humans evolved currently have more of their Pleistocene megafaunal diversity (the elephants and rhinos of Asia and Africa) compared to other areas such as Australia, the Americas, Madagascar and New Zealand, areas where early humans were non-existent. Based on this evidence, a picture arises of the megafauna of Asia and Africa evolving with humans, learning to be wary of them, and in other parts of the world the wildlife appearing ecologically naive and easier to hunt. This is particularly true of island fauna, which display a dangerous lack of fear of humans.
  The most convincing evidence of his theory is that 80% of the North American large mammal species disappeared within 1000 years of the arrival of humans on the Western Hemisphere continents. World wide extinctions seem to follow the migration of humans and to be most severe where humans arrived most recently and least severe where humans were originally – Africa (see figure at right). This suggests that in Africa, where humans evolved, prey animals and human hunting ability evolved together, so the animals evolved avoidance techniques. As humans migrated throughout the world and became more and more proficient at hunting, they encountered animals that had evolved without the presence of humans. Lacking the fear of humans that African animals had developed, animals outside of Africa were easy prey for human hunting techniques. It also suggests that this is independent of climate change
  Circumstantially, the close correlation in time between the appearance of humans in an area and extinction there provides weight to this theory. This is perhaps the strongest evidence, as it is almost impossible that it could be coincidental when science has so many data points. For example, the woolly mammoth survived on islands despite worsening climatic conditions for thousands of years after the end of the last glaciation, but they died out when humans arrived around 1700 BC. The megafaunal extinctions covered a vast period of time and highly variable climatic situations. The earliest extinctions in Australia were complete approximately 30,000 BP, well before the last glacial maximum and before rises in temperature. The most recent extinction in New Zealand was complete no earlier than 500 BP and during a period of cooling. In between these extremes megafaunal extinctions have occurred progressively in such places as North America, South America and Madagascar with no climatic commonality. The only common factor that can be ascertained is the arrival of humans.
  Climate Change
  The size of a short faced bear compared with a human.An alternative explanation offered by many scientists is that the extinctions were caused by climatic change following the last Ice Age. Critics object that since there were multiple Ice Ages in the evolutionary history of many of the megafauna, it is rather implausible that only after the last glacial would there be such extinctions.
  Some evidence weighs against this theory as applied to Australia. It has been shown that the prevailing climate at the time of extinction (40,000–50,000 BP) was similar to that of today, and that the extinct animals were strongly adapted to an arid climate. The evidence indicates that all of the extinctions took place in the same short time period, which was the time when humans entered the landscape. The main mechanism for extinction was likely fire (started by humans) in a then much less fire-adapted landscape. Isotopic evidence shows sudden changes in the diet of surviving species, which could correspond to the stress they experienced before extinction.

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2.1.3  native species declines

V1  【by: 优里西斯】

记得一篇阅读: 第一段: native species declines, 有人认为是因为nonnative species invade了,也有人认为是本地的一些环境改变,像污染之类的才是造成这个原因。这段作者没有给出他的point
第二段: 说2个研究的人说,如果是nonnative species造成的,那如果把nonnative species拿掉的话,native species 就不会减少了; 如果是本地环境变化造成的,那就算拿掉nonnative species 的话也会减少native species。 然后就分析了一个实验还是研究

V2  【by: xiaogutou28】

还遇到一个说dominance的。第一段开头说了一些定义啊啥的。然后给了个例子说某某湖的某鱼在另外一种鱼来invade之前数量已经decline了,原因是人们过度捕捞还有环境污染之类,后面有一道题目问这个例子说明了神马,或者问这个例子的作用是什么来着。第二段说有2个学者提出了一个理论,有题目问说这2个学者认为下面哪个assumption是正确的,或者问的是同意下面哪个说法。他们提出的理论是说要是外来物种侵犯本地的物种的话那引入一种外来的物种后,本地的物种数量会被影响然后下降。conversely,要是没有被影响数量下降的话,那么还有其他的原因云云。然后讲了个实验,在本地的草中间引入两种外来的草。实验的结果是并没有发现本地的那种草被外来物种影响数量下降。好像在实验这里问了一个削弱的。。不太记得了好像。。

V3  【by: wyolanda】
阅读关键字       
habitat degradation causes change in an area's biodiversity, nonnative species

V4  【by: fishwood  730】

nondominant species入侵,引起dominant species decline,但是科学家猜想是因为现有decline,然后才给nondominant species机会占领了统治权。然后做了个实验证明。具体的狗狗上写的很清楚咯,我也不重复啦。

V5  【by: serenashu】
外来植入入侵是否是成本地植物灭亡的原因?

V6  【by: fansail】原“2.1.3引进新物种”现和为一起

有一篇讲引进外来生物对当地生物影响的,大意是外来生物并不是威胁本地生物生存的原因。

V7  【by: xu_shining】
关于入侵物种引起原来物种的灭绝,还是原来物种的灭绝招致外来物种入侵。结论是后者。某科学家实验发现将入侵物种移除,反而造成了原来物种的继续降低。

V8  【by: 13873194104】

两段
第一段说普遍认为新物种导致了native species的减少,其实不然新物种可能不是原因而是consequence,真因是环境破坏
第二段有科学家做了实验,用grass什么的。移除了一个地方的两种新物种后native species没有减少   最后还继续论述了一下(没太看懂)   出的题目有难度

V9  【by: rainringting  V35】

一屏,开头说通常大家认为nonnative species是导致native species decline的原因,但是最近有两人的研究猜测,不是因为nonnative species导致native species不行,而是本来nonnative species所在的环境不行了,因此nonnative species才长得好,因此nonnative species长得好是consequence不是原因。然后论证了一番, 比如如果真的是nonnative species造成了native species不好,那么把nonnative species拔掉了native species就应该重新长好,但是实际上native species还是不好。

然后第二段出来了另外两人据此做实验,举了三个草的品种XYZ(拉丁文不记得首字母了)第一个是native,第二三个是nonnative(还是倒过来?),然后说把nonnative species都拿掉了,native还是长不好,证明了上一段的结论。进一步说,拿掉了nonnative species,长得好的是非草类的其他植物,因此证明了上一段两人的新观点是对的。

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2.1.4 lepidoptera★
更改答案(10/24日晚11点修改)
V1  【by: lamandel】
有一整篇gwd原题,四道题原封不动,确认(T-9-Q20-Q23:GWD-13-34~37)
新版答案为 BACD
原文搜索【by: XYXB】
A smallnumber of the forest species of lepidoptera (moths and butterflies, which existas caterpillars during most of their life cycle) exhibit regularly recurringpatterns of population growth and decline—such fluctuations in population areknown as population cycles. Althoughmany different variables influence population levels, a regular pattern such asa population cycle seems to imply a dominant, driving force.  Identification of that driving force,however, has proved surprisingly elusive despite considerable research. The commonapproach of studying causes of population cycles by measuring the mortalitycaused by different agents, such as predatory birds or parasites, has beenunproductive in the case of lepidoptera. Moreover, population ecologists’ attempts to alter cycles by changingthe caterpillars’ habitat and by reducing caterpillar populations have notsucceeded. In short, theevidence implies that these insect populations, if not self-regulating, may atleast be regulated by an agent more intimately connected with the insect thanare predatory birds or parasites.

Recent work suggests that this agent maybe a virus.  For many years, viraldisease had been reported in declining populations of caterpillars, butpopulation ecologists had usually considered viral disease to have contributedto the decline once it was underway rather than to have initiated it. Therecent work has been made possible by new techniques of molecular biology thatallow viral DNA to be detected at low concentrations in the environment.  Nuclear polyhedrosis viruses are hypothesizedto be the driving force behind population cycles in lepidoptera in part becausethe viruses themselves follow an infectious cycle in which, if protected from directsun light, they may remain virulent for many years in the environment, embeddedin durable crystals of polyhedrin protein. Once ingested by a caterpillar, thecrystals dissolve, releasing the virus to infect the insect’s cells. Late inthe course of the infection, millions of new virus particles are formed andenclosed in polyhedron crystals. These crystals reenter the environment afterthe insect dies and decomposes, thus becoming available to infect othercaterpillars.

One of theattractions of this hypothesis is its broad applicability. Remarkably, despitesignificant differences in habitat and behavior, many species of lepidopterahave population cycles of similar length, between eight and eleven years.  Nuclear polyhedrosis viral infection is onefactor these disparate species share.

T-9-20:GWD-13-34:
Which of the following, if true, would most weaken theauthor’s conclusion in lines 25-30?
A.New research reveals that the number ofspecies of birds and parasites that prey on lepidoptera has droppedsignificantly in recent years.
B.New experiments in which the habitats oflepidoptera are altered in previously untried ways result in the shortening oflepidoptera population cycles.
C.Recent experiments have revealed that thenuclear polyhedrosis virus is present in a number of predators and parasites oflepidoptera.
D.Differences among the habitats oflepidoptera species make it difficult to assess the effects of weather onlepidoptera population cycles.
E. Viral disease is typicallyobserved in a large proportion of the lepidoptera population.

T-9-21:GWD-13-35:
It can be inferred from the passage that the mortalitycaused by agents such as predatory birds or parasites was measured in anattempt to
A.develop an explanation for the existence oflepidoptera population cycles
B.identify behavioral factors in lepidopterathat affect survival rates
C.identify possible methods for controllinglepidoptera population growth
D.provide evidence that lepidopterapopulations are self-regulating
E.   determine the life stagesof lepidoptera at which mortality rates are highest

T-9-22:GWD-13-36:
The primary purpose of the passage is to              
A.describe the development of new techniquesthat may help to determine the driving force behind population cycles in Lepidoptera
B.    present evidence thatrefutes a particular theory about the driving force behind population cycles inLepidoptera
C.present a hypothesis about the driving forcebehind population cycles in Lepidoptera
D.describe the fluctuating patterns ofpopulation cycles in Lepidoptera
E.    question the idea that asingle driving force is behind population cycles in Lepidoptera

T-9-23:GWD-13-37:
According to the passage, before the discovery of newtechniques for detecting viral DNA, population ecologists believed that viraldiseases
A.were not widely prevalent among insectpopulations generally
B.affected only the caterpillar life stage oflepidoptera
C.were the driving force behind lepidopterapopulation cycles
D.attacked already declining caterpillarpopulations
E.    infected birds andparasites that prey on various species of lepidoptera

V2 【by: luoiszhong】
科学家之前就发现一个虫子(还是细菌? 类似caterpillar一样的蛹?)还是病毒神马的很小强,可以通过鸟类(?)传播(?)(问号意味着我在YY,我不确定),甚至还能到CRYSTAL里面存活?(是吗,这货怎么这么强)。这篇文正有点长,我考的很晕。

V3  【by: fansail】
GWD原题,毛毛虫那篇,似乎题目都没变

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2.1.5蟾蜍与青蛙★
V1  【by: sky7115】
一个比较蟾蜍和青蛙的eggs,举了三个品种,说一种怎么样强悍,在辐射下也很牛,另外两种就不太好。最后来了个However,说了一下存在个矛盾。将近一屏

V2  【by: zinniz】
frogs eggs。有青蛙还是什么的数量减少了,研究说是被UV射线照射了所以死了,这里是两种,H和B两种生物。但有一种物质的存在却能保护他们,这种是存在在另外一个species里的,反正名字很长。

V3  【by: nickshengmat】
阅读有一骗是说什么动物frog和什么之类的因为explosure U减少了但证明不是这样的还有可能是其他因素。

V4  【by: mystarbucks  700】
P1:  说青蛙/癞蛤蟆卵对太阳光中的紫外线照射的忍耐度不太一样,有些忍耐力很强,有些则很容易就被kill掉了。有一类很NB的青蛙就具有很高的耐受性;
P2:  说紫外线照射不仅会影响卵的生长,还会由此影响青蛙的免疫系统,
后面不太记得了,整篇不难,一平。

V5  【by: tallent】
还有一篇是生物的 关于一种酶的含量如果高 就能抵挡uv(太阳紫外线)

V6  【by: violetme】

toad and frog. 补充一点,UV是紫外线辐射。三种蛙,一种H更厉害,不怕辐射,另外两种H和B不太行,有了UV就萎了,只有把UV移去才能恢复正常。另外还讲到一个关于免疫的问题。文章末尾有讲到人类对蛙类的污染。

V7  【by: 知盛卿 700】

三种青蛙卵,大意是科学家发现第一种H的抗辐射能力好,其他2种(一个叫S,一个叫B....)被辐射过后容易减少.考了主旨,选阐述科学发现那个.

V8  【by: athena106 的同学】

一到是青蛙卵和紫外线的那个。
而且青蛙那个好像还变形了,她说,除了第一段一样,后两段都不一样。。。

V9  【by: rainringting  V35】

一屏,第一段说两个科学家做蛙类卵的孵化率field study,三个品种的卵拿来照紫外线,第一个品种因为含有某种酶,此酶的activity很活跃因此抵挡紫外线,所以孵化率仍然很高,另外两个的酶activities较低,所以孵化率就不行了,要减少紫外线照射孵化率才会回升。所以证明这个酶跟孵化率有关。 然后说到这个酶还会影响到蛙类的免疫系统。However免疫系统什么忘了,但是没考点。
第二段说到人类污染导致臭氧减少,紫外线升高,于是很多蛙类的孵化率降低可能是这个原因云云。
不是dumdumface提供的文字!第一段也不对,确定!

V10  【by: alex0795   710】

第二篇碰到了 将青蛙和uv射线的   大概和狗说的差不多   其中有一题试问驳斥作者观点   好像还有一题是说 除了牛逼的青蛙    另外两个不牛逼的青蛙 。。。。   根据原文定位就好了

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原文搜索:dumdumface (已有狗主人确认第一段为原文,但也有狗主人称不是这段,可能是GMAC出变体了,大家自行定夺,建议最好还是看下这段英文~)

Blaustein and his colleagues tested whether or not UV-B could be a factor in lowering the hatching rate of amphibian eggs. At two field sites, they divided the eggs of each of three amphibian species into three groups (Figure 3.6). The first group developed without any sun filter. The second group developed under a filter that allowed UV-B to pass through. The third group developed under a filter that blocked UV-B from reaching the eggs. For Hyla regilla, the filters had no effect, and hatching success was excellent under all three conditions. For Rana cascadea and Bufo boreas, however, the UV-B blocking filter raised the percentage of eggs hatched from about 60% to close to 80%.

The environmental programs of experimental embryology were a major part of the discipline when Entwicklungsmechanik was first established. However, it soon became obvious that experimental variables could be better controlled in the laboratory than in the field, and that a scientist could do many more experiments in the laboratory. Thus, field experimentation in embryology dwindled in the first decades of the twentieth century (see Nyhart 1995). However, with our increasing concern about the environment, this area of developmental biology has become increasingly important. Other recent work in this field will be detailed in Chapter 21.

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