TPO13: BIOLOGICAL CLOCKS
(2011-12-22 19:02:30)
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Biological Clocks
1.
a)
b)
c)
d)
解析:查字典:Consequentlymeans as a result. 释义来自科林斯高级学习词典。
Therefore:as a result of something that has just been mentioned。释义来自朗文当代词典。
2.
a)
b)
c)
d)
解析:回到原句“For instance, apparently normal daily periods of biological activity were maintained for about a week by the fungus Neurospora when it was intentionally isolated from all geophysical timing cues while orbiting in a space shuttle.”意思是:例如,当Neurospora真菌被放在一个围绕旋转地太空梭中有意地从所有地理物理时间线索中隔离开来时,它的一般生物活动日周期明显要持续一周。这是一个例子,本身不重要,我们往前看“By isolating organisms completely from external periodic cues, biologists learned that organisms have internal clocks.”意思是:通过把生物完全和外界周期线索隔离,生物学家了解到生物体是有内部时钟的。
3.
a)
b)
c)
d)
解析:选项四错,段落并没有做过这样的比较;
选项一对,段落第三句“The relations between animal activity and these periods, particularly for the daily rhythms, have been of such interest and importance that a huge amount of work has been done on them and the special research filed of chronobiology has emerged.”意思是:动物活动和这些周期的关系,尤其是每日韵律,太有趣太重要以至于在这方面做了大量工作并且特殊的时钟生物学研究出现了。因此选项三也对。
选项二对,段落第五句“Almost universally, biologists accept the idea that all eukaryotes (a category that includes most organisms except bacteria and certain algae) have internal clocks.”意思是:生物学一致同意一种想法:所有的Eukaryotes(一类除细菌和一些藻类之外的生物)都有内部钟。
4.
a)
b)
c)
d)
解析:查字典:Something that is persistent continues to exist or happen for a long time;释义来自科林斯高级学习词典;
5.
以下哪一项能表达出高亮句子的精华核心含义?错误选项改变重要含义或者遗漏精华信息。
Indeed, stability of the biological clock’s period is one of its major features, even when the organism’s environment is subjected to considerable changes in factors, such as temperature, that would be expected to affect biological activity strongly.
确实,生物钟时段的稳定性是最重要的特色之一,甚至当生物环境受制于一些因素的强烈变化,比如温度;这些因素会强烈影响到生物活动。
a)
b)
c)
d)
解析:选项一错,原句没有这样的因果关系,没有取决于的表达和含义。
选项三错,主干就错了,原句的主语应该是稳定性而不是环境因素。
选项四错,丢失了主干信息,没有提到稳定性。
6.
a)
b)
c)
d)
解析:根据circadian和deprived of environment定位。段落第三句“Like almost all daily cycles of animals deprived of environmental cues, those measured for the horseshoe crabs in these conditions were not exactly 24 hours.”意思是:与大多缺乏环境线索的动物的日活动周期一样,为鲎测量的那些日活动周期在这些情况下也不是精确地24小时。看下一句“Such a rhythm whose period is approximately- but not exactly – a day is called circadian.”意思是:这样的近似一天的周期被叫做生理节奏。再看下去“For different individual horseshoe crabs, the circadian period ranged from 22.2 to 25.5 hours.”意思是:对于单独的鲎来说,生理周期长度从22.2到25.5小时不等。看到这里,应该就能确定选项三是对的。选项一,二,四都没谈到过。
7.
a)
b)
c)
d)
解析:我们来看看倒数三句话“Typically, the animal’s daily internally generated cycle of activity continues without change. As a result, its activities are shifted relative to the external cycle of the new environment. The disorienting effects of this mismatch between external time cues and internal schedules may persist, like our jet lag, for several days or weeks until certain cues such as the daylight/darkness cycle reset the organism’s clock to synchronize with the daily rhythm of the new environment.”意思是:通常,动物内置的日活动周期会持续不变。因此,它的活动要随着新环境外部周期进行调整。这种外部时间线索和内置计划不匹配的混乱影响会持续,就像我们坐飞机的时差一样会持续几天或几周直到一些线索如日照和黑夜循环重置生物钟来与新环境活动节奏同步。因此答案是选项一。
8.
a)
b)
c)
d)
解析:段落举了crayfish和horseshoe crab的例子。其中没有列举,没有过程描述,没有对比。所以答案只能选第三项。
9.
a)
b)
c)
d)
解析:查字典:Duration:the length of time that something lasts;释义来自剑桥高级学习词典。
10.
a)
b)
c)
d)
解析:到段落原句往前看,先看到前一句“Such a rhythm whose period is approximately – but not exactly- a day is called circadian.”意思是:这样一种长短近似一天的节奏被称为生理节奏。这是一个定义不能说明问题,再往前看到段落第三句“Like almost all daily cycles of animals deprived of environmental cues, those measured for the horseshoe crabs in these conditions were not exactly 24 hours.” 与大多缺乏环境线索的动物的日活动周期一样,为鲎测量的那些日活动周期在这些情况下也不是精确地24小时。
11.
a)
b)
c)
d)
解析:原句“Such an external cue not only coordinates an animal’s daily rhythms with particular features of the local solar day but also – because it normally does so day after day – seems to keep the internal clock’s period close to that of Earth’s rotation.”意思是:这样的一个外部线索不仅调整一个动物每日节奏和当地太阳日的特点而且还保证内部时钟长短与地球旋转长度一致,因为它通常都是日复一日的发生。
12.
a)
b)
c)
d)
解析:查字典:sustained: continued for a long time. 释义来自剑桥高级学习词典。
13.
Because the internal signals that regulate waking and going to sleep tend to align themselves with these external cues, the external clock appears to dominate the internal clock.
因为管理起床和睡觉的信号倾向于按照外部线索调整自己,所以是外部时钟控制内部时钟。
解析:解题关键在于these external cues,这证明之前要提供足够关于那些外部线索。发现第二句和第四句都有external cue,但是因为第五句话的this drift和前一句衔接紧密。而第三句话之前的this synchronization of the period of the internal cycle正好可以对应上插入句子的align themselves with these external cues.因此答案是第二个插入口。
14.
The activity of animals is usually coordinated with periodically recurring events in the environment.
动物的活动通常要与环境中周期性重复发生的事件协调。
a)
b)
c)
d)
e)
f)
解析:选项一错,原文第一句“Survival and successful reproduction usually require the activities of animals to be coordinated with predictable events around them”
选项二对,第二段说内部时钟是稳定的,不容易外界影响的,关于基因决定可以看到第三段第三句“Yet despite this synchronization of the period of the internal cycle, the animal’s timer itself continues to have its own genetically built-in period close to , but different from, 24 hours.”
选项三错,第二段中提到温度的改变不足以影响到动物时钟的长度。
选项四对,第二段的主要内容。
选项五错,根本没提到过与人的影响的对比。
选项六对,第三段的主要内容。
因此,答案是:2,4,6;
现象解释说明文
第一段引出动物成功生存和繁殖需要把自己的活动与环境中可预测的周期性事件协调一致。比如:动物睡觉、饮食、繁殖、新陈代谢、分泌酶和荷尔蒙都要与周期性环境事件比如:太阳日、潮起潮落、月运周期和四季变化。但问题是动物的这种计划是受制于外部线索,比如日出日落,还是取决于内部时钟。科学家们一致认为eukaryotes都有内部时钟。做了一个实验:通过隔离外部线索,来了解内部时钟。举了Neurospora的例子。当这种真菌被放到绕地球旋转的太空梭中,故意与任何地理物理线索隔开,它的日常生物活动时段还是保持了一个星期。
第二段先举了一个crayfish的例子,来说明日常计划的保持不变性,一直调解眼睛视力来适应白天和黑夜。接着举了horseshoe crabs的例子,说放到黑暗中一年,大脑活动节奏还是持续不变的,调节眼睛适应强光和弱光。这些没有环境因素的动物日周期都不是精确的24小时,这个时段叫做生理节奏。每个horseshoe crab个体的生理节奏长度不同,范围是22.2到25.5小时。这种动物生物钟时段的稳定性是重要特性,即使环境因素改变也不会受到影响。然后再举了一个例子来证明这种内在节奏的持续稳定性,当外部周期发生改变而内部周期却恒定不变,这样就导致了disorientation。而这种mismatch会持续几天甚至几周,比如坐飞机的时差,直到一些外部环境线索重置生物钟。
第三段讲动物需要自然周期信号来维持精确24小时的周期。这种外部线索不仅协调动物的日节奏还保持内部生物钟长短接近地球自转时间。如果没有外部线索,这种内外差异就会不断积累,而且内部调节活动的生物钟一天也会相对一个太阳日不断漂移。说对于果蝇产卵和松鼠跑轮子做过此类研究。然后说在恒定的黑暗中突然放出15分钟的强光会重新设定动物的生理节奏。其实目的就是说内部节奏是受到外部有规律的环境循环控制的。举了信鸽用太阳当指南针的例子。