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
医学
A、Several hundred. B、Around one hundred. C、A new one every several hours. D、Less than the size of his body. B题目问的是成熟的鹦鹉螺一般有多少个膛室
A、Several hundred. B、Around one hundred. C、A new one every several hours. D、Less than the size of his body. B题目问的是成熟的鹦鹉螺一般有多少个膛室
admin
2018-05-06
23
问题
Of all the animals that live in the sea, (26) crustaceans (甲壳纲动物) have the most unusual of reaching maturity. The chambered nautilus (鹦鹉 ) is a perfect example of how this happens.
Like most crustaceans (卤虫) , these creatures have hard, permanent shells with many sections of crustacean must produce a new section of shell that will be more suitable for its larger body.
In the beginning stages of growth, the crustacean’s body occupies a small section at back of the shell. As it begins to mature, the body emerges from the back of the shell and bet to (27) take up space closer and closer to the entrance of the shell. It is at this stage of development that the nautilus is especially vulnerable to predators. In order to remain protected the animal must produce a new section of shell in which to grow.
In order to produce the new section of shell, the nautilus secretes an enzyme which surrounds the entrance of the shell and forms a temporary support for the addition of charged, calcium compounds in the seawater. (28) The process takes several hours, but when it is completed, a new section of shell is available for the nautilus to move into. As the animal moves into the new chamber, the previous chamber is left empty. Over time, the shell of the chambered nautilus can become much larger than the animals itself.
(29) An adult chambered nautilus contains an average of a hundred sections. Some specimens have been found with several hundred sections and several feet in length. Most of the larger animals (30) were found in the cold waters of the North Atlantic. It is not know how long the chambered nautilus can live, but scientists have calculated from the shell chambers of these larger crustaceans that their shells may have been slowly growing for hundreds of years.
26.What is the main idea of this talk?
27.When is a nautilus vulnerable to predators?
28.How long does it take produce a new section of shell?
29.How many chambers does an adult nautilus usually have?
30.Where were most larger nautiluses found?
选项
A、Several hundred.
B、Around one hundred.
C、A new one every several hours.
D、Less than the size of his body.
答案
B
解析
题目问的是成熟的鹦鹉螺一般有多少个膛室。由定位句可知,有上百个,故选B。
转载请注明原文地址:https://kaotiyun.com/show/C0T3777K
本试题收录于:
医学博士外语题库考研分类
0
医学博士外语
考研
相关试题推荐
男性,43岁,风湿性心脏病史多年。近1周活动后出现心悸,胸闷明显,伴气促。查体:血压140/50mmHg,心率100次/分,S1正常、S2稍↑,单一L2.3舒张期杂音3/6哈气样,X线片见心影扩大,以左室大为主,双肺淤血征,超声心动图提示风湿性主动脉瓣关闭
女,34岁。阵发性腹痛4天,伴有恶心、呕吐,起病以来肛门未排便排气,3年前因胆囊结石行胆囊切除术,正值月经中期。查体:脉搏120次/mln,血90/60mmHg,腹饱满右侧腹部较对侧膨隆,有压痛、反跳痛及肌紧张。右下腹腔穿刺抽出少量暗红色液体。血红蛋白11
Themethod______furtherinvestigation.
A、HeartattacksB、StrokesC、DrugaddictionD、CerebralhaemorrhageD录音讲到很多医生都在使用一种叫作streptokinase的药,这种药剂有时会带来一些问题,甚至会引起bleedingi
Englishspeakerspickuppitchintherighthemispheresoftheirbrains,butspeakersofcertainotherlanguagesperceiveiton
Itwouldbewildlyoptimistictobelievethattheseadvancesoffsetsuchalargereductioninfarmland.
Theremaybealinkbetweencreativityandmentaldisorders,butitisprobablynotinthewaythatyouthink.Thereisawidesp
Scientistsusedtobelieveadultbrainsdidnotgrowanynewneurons,butithasemergedthatnewneuronscansproutinthebrai
A、Allanimalsinthebush.B、Theremnantofthesameprimevalprogramming.C、Thesameprimevalprogramming.D、Allanimalsinthe
A、Tolosesomeweight.B、Totakeafewmoretests.C、Tosleeponthreepillows.D、Toeatsmaller,lightermeals.B题目问下列哪一项不是医生的
随机试题
美国行政组织改革的突出特点是
阅读莫泊桑《米龙老爹》中的文字,然后回答问题。那匹安静的马等候他的主人。米龙老爹骑了上去,教它用“大颠”的步儿穿过平原走开了。一小时以后,他又看见两个归营的骑兵并辔而来。他一直对准他们赶过去,又用德国话喊着:“救人!救人!”那两个普兵认
关于乳腺癌锁骨上淋巴结及腋窝淋巴结可用一个野照射,下列叙述中正确的是
A.全心衰竭B.右心衰竭C.右房衰竭D.左心衰竭E.左房衰竭患者,女性,60岁。二尖瓣关闭不全病史40年,出现双下肢水肿,劳力性呼吸困难,可能诊断为
航空货运代理公司之所以能够产生并迅速发展起来,是因为至今航空公司的服务基本没有走出机场。()
属于家庭财产保险的基本险种的有()
个人经营贷款可采取的还款方式有()。
GoldenTouchConstructionis______.
现代计算机技术中,下列不是度量存储器容量的单位是
Whatdoesthespeakerdomostprobably?
最新回复
(
0
)