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
Studies of the Weddell seal in the laboratory have described the physiological mechanisms that allow the seal to cope with the e
Studies of the Weddell seal in the laboratory have described the physiological mechanisms that allow the seal to cope with the e
admin
2014-09-18
83
问题
Studies of the Weddell seal in the laboratory have described the physiological mechanisms that allow the seal to cope with the extreme oxygen depriva- tion that occurs during its longest dives, which can extend 500 meters below the ocean’ s surface and last for over 70 minutes. Recent field studies, however, suggest that during more typical dives in the wild, this seal’ s physiological behavior is different.
In the laboratory, when the seal dives below the surface of the water and stops breathing, its heart beats more slowly, requiring less oxygen, and its arteries become constricted, ensuring that the seal’ s blood remains concentrated near those organs most crucial to its ability to navigate underwater. The seal essentially shuts off the flow of blood to other organs, which either stop functioning until the seal surfaces or switch to an anaerobic(oxygen-independent)metabolism. The latter results in the production of large amounts of lactic acid which can adversely affect the PH of the seal’ s blood but since the anaerobic metabolism occurs only in those tissues which have been isolated from the seal’s blood supply, the lactic acid is released into the seal’ s blood only after the seal surfaces, when the lungs, liver, and other organs quickly clear the acid from the seal’s blood stream. Recent field studies, however, reveal that on dives in the wild, the seal usually heads directly for its prey and returns to the surface in less than twenty minutes. The absence of high levels of lactic acid in the seal’ s blood after such dives suggests that during them, the seal’ s organs do not resort to the anaerobic metabolism observed in the laboratory, but are supplied with oxy- gen from the blood. The seal’ s longer excursions underwater, during which it appears to be either exploring distant routes or evading a predator, do evoke the diving response seen in the laborato- ry. But why do the seal’ s laboratory dives always evoke this response, regardless of their length or depth? Some biologists speculate that because in laboratory dives the seal is forcibly sub- merged, it does not know how long it will remain underwater and so prepares for the worst.
The passage provides information to support which of the following generalizations?
选项
A、Observations of animals’ physiological behavior in the wild are not reliable unless verified by laboratory studies.
B、It is generally less difficult to observe the physiological behavior of an animal in the wild than in the laboratory.
C、The level of lactic acid in an animal’s blood is likely to be higher when it is searching for prey than when it is evading predators.
D、The level of lactic acid in an animal’s blood is likely to be lowest during those periods in which it experiences oxygen deprivation.
E、The physiological behavior of animals in a laboratory setting is not always consistent with their physiological behavior in the wild.
答案
E
解析
文章支持下列哪个观点?A.动物生理行为在野外的观察除非得到了实验室验证,否则是不可靠的。正好说反,原文海豹的潜水生理机制实验室中的观测结果是不完全的,要用野外观测来修正。B.“less difficult to observe”文中未涉及观察难度。C.“lactic acid in an animal’s blood”暂且不论此观点用在海豹身上对不对,就是正确也不能推广到泛指任意一种动物。D.同C。E.正确。动物的野外生理行为并不总和实验室中一致。此结论只要能有一例,就可以说是“not always consistent”,文中海豹就是这样一个例子。
转载请注明原文地址:https://kaotiyun.com/show/0ctO777K
本试题收录于:
GMAT VERBAL题库GMAT分类
0
GMAT VERBAL
GMAT
相关试题推荐
Theydidnotfind______topreparefortheworstconditionstheymightmeet.
It’simportanttolocateindustriesinareaswhereasupplyofrawmaterialsis______.
Itseemslikeeverydaythere’ssomenewresearchaboutwhetherourfavoritedrinksaregoodforus.Oneday,sciencesaysagla
"Equalpayforequalwork"isaphraseusedbytheAmericanwomenwhofeelthattheyareunfairlytreatedbysociety.Theysayi
Mr.WangteachesEnglishinamiddleschool.Helikeshisworkverymuch.Hewanted【C1】______ateacherevenwhenhewasayoung
Gettingplentyofexerciseisveryimportant.Ienjoyswimmingverymuch.LastsummerIwenttothe【C1】______everyday.Iplant
Themulti-billion-dollarWesternpopmusicindustryisunderfire.ItisbeingblamedbytheUnitedNationsforthedramaticris
TheChinesehaveusedamethodcalledacupuncture(针炙)toperformoperationsforabout4,000yearswithoutputtingthepatientto
TheperformanceoftheEnglishteamwas________.Theyplayedmuchworsethanexpected.
Alltheirattemptsto_________thechildfromtheburningbuildingwereinvain.
随机试题
艺术意象的创造和产生过程可以分为以下两个阶段()
函数f(x)在点x=x0处连续是f(x)在x0处可导的【】
患者,女,16岁。间断性头痛1个月,时轻时重,头痛如裹,肢体困重,胸闷纳呆,大便不实,苔白腻,脉濡。近日患者恶心呕吐可加
“部分容积效应”中的“部分容积”的含义是
A、阿利吉仑B、替米沙坦C、哌唑嗪D、坦洛新(坦索罗辛)E、卡托普利属于肾素抑制剂的药物是
《建设工程质量管理条例》规定,建设工程质量保修书中应当明确建设工程的()等。
假设其他条件不变,下列计算方法的改变会导致应收账款周转天数减少的有()。
国家出资企业因增资致使国家不再拥有所出资企业控股权的,须由国资监管机构报本级人民政府批准。()
ABC公司下设A、B两个投资中心,没有持有金融资产,A投资中心的平均资产为700万元,平均经营负债有350万元,部门投资报酬率为20%;B投资中心的部门投资报酬率为22%,剩余收益为105万元,平均经营负债为320万元;ABC公司对A投资中心要求的平均最低
无因管理是指没有法定或约定义务,为避免造成损失(损失包括自己也包括他人,或者仅为他人,主动管理他人事务或为他人提供服务的行为。根据这一定义,下列属于无因管理的是:
最新回复
(
0
)