首页
登录
职称英语
Hitherto, there is no evidence yet that would definitively prove whet
Hitherto, there is no evidence yet that would definitively prove whet
游客
2025-02-22
9
管理
问题
Hitherto, there is no evidence yet that would definitively prove whether or
not some dinosaurs were warm-blooded, but scientists have begun to investigate
oxygen isotopic abundances in the annual growth bands of teeth or bones of high
Line latitude, hence seasonally influenced, terrestrial dinosaurs. The ratio of oxygen
(5) isotopes depends on temperature, and an absence of seasonal variations in
oxygen 18—a heavy version of the common oxygen 16 atom-would strongly
suggest that the animals maintained a constant internal temperatures. Such a
finding would not, however, constitute "proof" that dinosaurs were warm
blooded, as there are external mechanisms that cold-blooded animals employ to
(10) regulate body temperatures and thereby influence metabolic rates. More
nettlesome is that proof would have to come from discovery of intact dinosaur
remains in which the soft tissue had not been replaced or altered, and from
which the biomolecules responsible for thermoregulation could be extracted,
identified and characterized. Such a proof is unlikely, as it would require an
(15) almost impossible level of preservation over 65 million years, plus the advent of
biotechnology that does not yet exist. [br] According to the passage, the most severe problem currently facing scientists in conclusively determining whether certain dinosaurs were warm-blooded is
选项
A、proving that thermoregulation is the primary means by which metabolic rates are influenced
B、developing a way of distinguishing between oxygen 18 and oxygen 16
C、showing that an absence of seasonal variation in oxygen 16 implies a constant internal temperature
D、finding a sample of dinosaur tissue which has survived 65 million years in a relatively intact form
E、determining which species of dinosaurs were most likely to be warm-blooded, and focusing research there
答案
D
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3968233.html
相关试题推荐
Hitherto,thereisnoevidenceyetthatwoulddefinitivelyprovewhet
Hitherto,thereisnoevidenceyetthatwoulddefinitivelyprovewhet
Whentheevidenceis______,wecanbemoreconfidentofthehistoricalscenarios
Scientistsresearchinghypnosishaveuncoveredevidencethatcounte
Scientistsresearchinghypnosishaveuncoveredevidencethatcounte
Scientistsresearchinghypnosishaveuncoveredevidencethatcounte
Scientistsresearchinghypnosishaveuncoveredevidencethatcounte
FALLACY:A、sustainingevidenceB、believabletheoryC、legitimateanalysisD、absolu
Whenevidenceis(i)______,reasonablepeoplemaydemur,butwhenfirmscientifi
Evidencethattheuniverseisexpanding(i)______ourperceptionofthecosmosan
随机试题
读书或书籍的享受素来被视为有修养的生活上的一种雅事,而在一些不大有机会享受这种权利的人们看来,这是一种值得尊重和妒忌的事。当我们把一个不读书者和一个读书
Don’treadinsuchapoorlightoryou’ll______youreyes!A、destroyB、ruinC、stra
【S1】[br]【S4】A、determinedB、decidedC、proposedD、doubtedBSoOfcom...hasdecide
关于脂肪变性,下列哪一项是正确的()A.慢性肝淤血时,肝小叶中央区脂肪变性最
锌有助于减轻炎症和促进痤疮愈合,治疗寻常痤疮用锌的最佳剂量是A.每日300~40
对浸水飞散试验,先在60℃±O.5℃恒温水槽中养生(),然后取出在室温中放置。A
用于治疗金属和类金属中毒的解毒剂不包括下列哪项?A.亚甲蓝 B.依地酸二钠钙
下列关于“菲利普斯曲线”的说法中,不正确的是:A、横轴代表失业率,纵轴代表工资上
在信号检测论中,P(y/SN)指( )A.正确否定率 B.虚报率 C.漏报
关于可撤销合同中撤销权行使的说法,正确的是()。A.受胁迫的当事人应当自胁
最新回复
(
0
)