The Internal Body Clock

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题目与答案

1. support for an earlier finding from experiments on insects
   • A
   • B
   • C
   • D
   • E
   • F

   答案：F

   原文定位：But in 1971, scientists at the California Institute of Technology working with fruit flies found evidence for something truly amazing. Fruit flies appeared to have genes affecting the daily rhythm of their behavior – suggesting that there are ‘clocks’ inside each of their cells. Further evidence for this emerged in 1995, when researchers at Massachusetts General Hospital isolated nerve cells from the SCN, and found they kept up a circadian cycle without help from daylight

   同义替换：「support for an earlier finding」↔「Further evidence for this emerged」，「experiments on insects」↔「fruit flies」

2. criticism of the way some research data was analysed
   • A
   • B
   • C
   • D
   • E
   • F

   答案：D

   原文定位：Most of the remainder contained blunders ranging from faulty mathematics to basic errors in statistics, while the handful of positive studies were explicable as flukes

   同义替换：「criticism of the way some research data was analysed」↔「contained blunders ranging from faulty mathematics to basic errors in statistics」

3. reference to a basic test on a plant
   • A
   • B
   • C
   • D
   • E
   • F

   答案：A

   原文定位：Intrigued by the way some flowers open and close their leaves each day, Jean-Jacques de Mairan put a heliotrope in a darkened room and observed the effect

   同义替换：「a basic test on a plant」↔「put a heliotrope in a darkened room and observed the effect」，「plant」↔「heliotrope」

4. a statement that the length of natural cycles varies slightly between living things
   • A
   • B
   • C
   • D
   • E
   • F

   答案：E

   原文定位：Following de Mairan’s pioneering work, other researchers found that when deprived of the cues provided by sunlight, organisms settle down to ‘free-running’ cycles that are close to, but rarely exactly, 24 hours. In the case of humans, the cycle is typically around 24.5 hours long

   同义替换：「the length of natural cycles」↔「‘free-running’ cycles」

5. reference to a theory that became popular with the public
   • A
   • B
   • C
   • D
   • E
   • F

   答案：C

   原文定位：During the 1970s, best-selling books began to emerge claiming such phenomena were manifestations of so-called biorhythms, a set of three cycles governing physical, emotional and intellectual traits

   同义替换：「a theory that became popular with the public」↔「best-selling books began to emerge」，「theory」↔「biorhythms」

6. An overview of research into the existence of the internal ‘clock’

   Towards the end of the 1960s, research into the SCN, which is located in the hypothalamus led chronobiologists to believe they had found the internal ‘clock’ at last. Their theory was based on the fact that certain hormones that regulate the timing of physical functions are controlled by the SCN. The SCN is able to perceive 19_____ as a result of connections to the eye.

   答案：daylight

   原文定位：Linked to photosensitive cells in the eye, the SCN senses daylight and triggers the release of hormones like melatonin, which keep body functions in synchronization with the time of day

   同义替换：「perceive」↔「senses」，「connections to the eye」↔「Linked to photosensitive cells in the eye」

7. Several years later, research involving 20_____ showed that the timing of their normal actions

   答案：fruit flies

   原文定位：But in 1971, scientists at the California Institute of Technology working with fruit flies found evidence for something truly amazing. Fruit flies appeared to have genes affecting the daily rhythm of their behavior – suggesting that there are ‘clocks’ inside each of their cells

   同义替换：「research involving」↔「working with」

8. was regulated by certain 21_____ or ‘clocks’, in their cells. Thus the internal ‘clock’ is not an individual mechanism, as previously thought, but exists within each cell.

   答案：fruit flies

   原文定位：But in 1971, scientists at the California Institute of Technology working with fruit flies found evidence for something truly amazing. Fruit flies appeared to have genes affecting the daily rhythm of their behavior – suggesting that there are ‘clocks’ inside each of their cells

9. Other scientists went on to conduct experiments in the dark that proved that a 22_____ was maintained by individual SCN cells.

   答案：circadian cycle

   原文定位：Further evidence for this emerged in 1995, when researchers at Massachusetts General Hospital isolated nerve cells from the SCN, and found they kept up a circadian cycle without help from daylight

   同义替换：「individual SCN cells」↔「nerve cells from the SCN」，「was maintained」↔「kept up」

10. 23-24 Which TWO of the following problems are stated as being linked with the internal ‘clock’?
    • a decrease in output in workplaces without windows to let in natural light
    • a failure among workers on night-shifts to perform tasks
    • an increase in casualties on the roads at specific times of day
    • a decline in efficiency on certain days in a number of fixed cycles
    • a rise in mood swings dependent on the appearance of the Sun

    答案：a failure among workers on night-shifts to perform tasks,an increase in casualties on the roads at specific times of day

    原文定位：When an individual’s ‘clock’ is knocked out of synchronization through having to work at night or go on long-haul flights, that person can be left utterly unable to think or act. Yet even when these ‘clocks’ work correctly, the natural rhythms of alertness they generate prove dangerous: traffic accident statistics show two deadly peaks, at 4 a.m. and again twelve hours later when people are at their least alert

    同义替换：「night-shifts」↔「work at night」，「failure to perform tasks」↔「unable to think or act」，「casualties」↔「traffic accident」，「specific times of day」↔「4 a.m. and again twelve hours later」

11. 25-26 Which TWO of the following issues relating to internal ‘clocks’ remain to be solved, according to information in the passage?
    • the precise length of the free-running daily cycle in different animals
    • the reason for ‘clocks being temporarily driven out of synchronisation
    • the reason for living beings forming a connection with the Sun’s rhythms
    • the way in which all ‘clocks’ in a single organism are able to stay in step with one another
    • the location of the ‘clocks’ across the whole range of living organisms

    答案：the way in which all ‘clocks’ in a single organism are able to stay in step with one another,the reason for living beings forming a connection with the Sun’s rhythms

    原文定位：But how do all the biochemical ‘clocks’ inside their cells stay in synchronization and why did organisms bother to acquire a link with sunlight? So far, no one knows, though there are several theories

    同义替换：「living beings」↔「organisms」，「forming a connection with the Sun’s rhythms」↔「acquire a link with sunlight」，「stay in step with one another」↔「stay in synchronization」