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
The plant called the scarlet gilia can have either red or white flowers. It had long been thought that hummingbirds, which forag
The plant called the scarlet gilia can have either red or white flowers. It had long been thought that hummingbirds, which forag
admin
2015-05-25
34
问题
The plant called the scarlet gilia can have either red or white flowers. It had long been thought that hummingbirds, which forage by day, pollinate its red flowers and that hawkmoths, which forage at night, pollinate its white flowers. To try to show that this pattern of pollination by colors exists, scientists recently covered some scarlet gilia flowers only at night and others only by day: plants with red flowers covered at night became pollinated; plants with white flowers covered by day became pollinated.
Which of the following, if true, would be additional evidence to suggest that hummingbirds are attracted to the red flowers and hawkmoths to the white flowers of the scarlet gilia?
选项
A、Uncovered scarlet gilia flowers, whether red or white, became pollinated at approximately equal rates.
B、Some red flowers of the scarlet gilia that remained uncovered at all times never became pollinated.
C、White flowers of the scarlet gilia that were covered at night became pollinated with greater frequency than white flowers of the scarlet gilia that were left uncovered.
D、Scarlet gilia plants with red flowers covered by day and scarlet gilia plants with white flowers covered at night remained unpollinated.
E、In late August, when most of the hummingbirds had migrated but hawkmoths were still plentiful, red scarlet gilia plants produced fruit more frequently than they had earlier in the season.
答案
D
解析
The results reported in the last sentence of the passage suggest that hummingbirds do pollinate red-flowered plants and that hawkmoths do pollinate white-flowered plants. But to prove that they are attracted preferentially to those colors requires knowing whether they also pollinate flowers of the other color that are uncovered during their respective foraging hours—white flowers uncovered during hummingbirds’ daytime hours, and red flowers uncovered during hawkmoths’ nocturnal hours. Choice D states that such plants remain unpollinated, so it is the correct answer. Of the other options, both Choices C and E could suggest the opposite of what is required, so they are incorrect. Choice A is incorrect because the comparative frequency at which uncovered gilia flowers are pollinated has no bearing on the argument. Likewise, the presence of some quantity of unpollinated flowers of either color does not affect the argument, so Choice B is also incorrect.
转载请注明原文地址:https://kaotiyun.com/show/IujO777K
本试题收录于:
GRE VERBAL题库GRE分类
0
GRE VERBAL
GRE
相关试题推荐
Alawyerfriendofminehasdevotedherselftotheserviceofhumanity.Herspecialareaiscalled"publicinterestlaw".Man
Inwhatnowseemsliketheprehistorictimesofcomputerhistory,theearlypost-warera(战后时期),therewasaquitewidespreadcon
_________language,mathsandhistory,thechildrenarealsotaughtmusicandart.
Concerningmoneyoranythingelse,conflictsbetweenhusbandandwifeusuallyreflectapowerstruggle.Conflictsbetweenparent
Traditionally,universitieshavecarriedouttwomainactivities:researchandteaching.Manyexpertswouldarguethatboththes
Fiftyapplicantsforajobweregivenscoresfrom1to5ontheirinterviewperformance.Theirscoresareshowninthetableabo
Inasampleofpatientsatananimalhospital,30percentarecatsand60percentarenotdogs.Whatfractionofthosepatients
Howmanyreallysufferasaresultoflabormarketproblems?Thisisoneofthemostcriticalyetcontentioussocialpolicyques
Theorganizersoftomorrow’soutdoorconcertannouncedthatitwillgoontomorrowonscheduleunlessbadweatherisforecasto
随机试题
畸形工件的基准选择一般情况下是()。
【背景资料】A、B两座相同的仓库项目,总建筑面积7000m2。施工时分A、B分区,项目经理下分设两名栋号经理,每人负责一个分区,每个分区又安排了一名专职安全员。项目经理认为,由栋号经理负责每个栋号的安全生产,自己可以不管理安全事项。A区
下列不是产生淹塔的原因是()。
一些心理学家声称,人们出门在外时可能会感到孤独。
临床上最常见的输血反应是
应置于干燥阴凉处或2~10℃冷藏保存的药物是()
教育改革的核心是【】
六声调式并不能作为一种单独的调式,它只是在五声音阶中增加一个偏音,或是在七声音阶中减少________而形成的一种临时的调式。
上海市人民政府发布的《上海市城镇职工基本医疗保险办法》属于()。
2014年1~11月我国货物运输情况2013年1~10月我国货物运输总量最大的领域是:
最新回复
(
0
)