杯具 失约而是二 狗还是要放滴 狗大大地有－－继续＋＋＋＋

papaya730

这么肥的狗？好人啊，楼主，祝你申请到理想的学校！

XYXB

如答案贴错，请各位指出噢，谢谢
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

tamiying

感谢楼主啊

simpleru

狗狗帖必须支持啊~

zafteria

感谢LZ的加菲狗

bobepop

楼主V5!

hannan518

LZ实在是太强大了阿

yyx

谢谢lz!!!祝申请顺利！

killerinJP

lz的记忆力镇强大阿~！！！

killerinJP

探中介的口气是 最好不要  不过这种东西谁又能说得清楚 想好了选个好日子就去考吧  


想起早上贪小便宜把分report 到几所dream school了  希望影响不大  哎  今天还真是手贱

-- by 会员 lamandel (2010/10/22 16:01:12)

那是因为你觉得你这次应该会比上次考得好啊~

那你就用第一次的成绩了？

-- by 会员 killerinJP (2010/10/22 16:19:02)