The idea of a fish being able to generate electricity strong enough to light lamp bulbs—or even to run a small electric motor—is

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问题     The idea of a fish being able to generate electricity strong enough to light lamp bulbs—or even to run a small electric motor—is almost unbelievable, but several kinds of fish are able to do this. Even more strangely, this curious power has been acquired in different ways by fish belonging to very different families.
    Perhaps the best known are the electric rays (鳐鱼),or torpedoes (水雷鱼),of which several kinds live in warm seas. They possess on each side of the head, behind the eyes, a large organ consisting of a number of cells which contain a series of flat electric plates. One side, the negative side, of each plate, is supplied with very fine nerves, connected with a main nerve coming from a special part of the brain. Current passes from the upper, positive side of the organ downwards to the negative, lower side. Generally it is necessary to touch the fish in two places, completing the circuit, in order to receive a shock.
    Another famous example is the electric eel (鳗鱼).This fish gives an even more powerful shock. The system is different from that of the torpedo in that the electric plates run along the length of its body and are supplied with nerves from the spinal cord (脊髓). Consequently, the current passes along the fish from head to tail. The electric organs of these fish are really altered muscles and like all muscles, they tend to tire easily, so they are not able to produce electricity for very long.
    The power of producing electricity may serve these fish both for defense and attack. If a large enemy attacks, the shock will drive it away; but it appears that the electric eel uses its current most often against smaller fish.
The electric plates on the electric eel______.

选项 A、run along the length of its body
B、are found on sides of its head
C、are located in its head
D、are in its tail

答案A

解析 本题是一道具体细节题。问电鳗鱼身上的电极板是如何分布的。利用查阅式阅读法,我们可以在文章的第三段中找到相关的内容。这段指出,另外一个广为人知的例子是电鳗,这种鱼的电击强度更大。它的放电系统与水雷鱼不同。在该系统中,电极片遍布全身,极片神经与脊髓相连,这样,电流便不断地流经全身,由头至尾流动。因此,本题的正确答案应是A“遍布全身”。
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