首页
登录
职称英语
The idea of a fish being able to generate electricity strong enough to light
The idea of a fish being able to generate electricity strong enough to light
游客
2024-08-07
6
管理
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, or torpedoes, 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 hexagonal shaped cells rather like a honeycomb. The cells are filled with a jelly-like substance, and contain a series of fiat 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.
The strength of this shock depends on the size of the fish, but newly born ones only about 5 centimetres across can be made to light the bulb of a pocket flashlight for a few moments, while a fully grown torpedo gives a shock capable of knocking a man down, and, if suitable wires are connected, will operate a small electric motor for several minutes.
Another famous example is the electric eel. This fish gives an even more powerful shock. The system is different from that of the torpedo in that the electric plates run longitudinally and are supplied with nerves from the spinal cord. 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 are apt to tire, so they are not able to produce electricity for very long.
The electric catfish of the Nile and of other African fresh waters has a different system again, by which current passes over the whole body from the tail to the head. The shock given by this arrangement is not so strong as the other two, but is none the less unpleasant. The electric catfish is a slow, lazy fish, fond of gloomy places and grows to about 1 metre long; it is eaten by the Arabs in some areas.
The power of producing electricity may serve these fish both for defence and attack. If a large enemy attacks, the shock will drive it away; but it appears that the catfish and the electric eel use their current most often against smaller fish, stunning them so that they can easily be overpowered.
For answers 51-55, mark
Y(for YES) if the statement agrees with the information given in the passage;
N (for NO) if the statement contradicts the information, given in the passage;
NG(for NOT GIVEN) if the information is not given in the passage. [br] The electric plates on the electric eel are supplied with nerves from its brain.
选项
A、Y
B、N
C、NG
答案
B
解析
由第四段可知The electric plates on the electric eel are supplied with nerves from the spinal cord而不是its brain。
转载请注明原文地址:https://tihaiku.com/zcyy/3710035.html
相关试题推荐
Theideaofafishbeingabletogenerateelectricitystrongenoughtolight
Theideaofafishbeingabletogenerateelectricitystrongenoughtolight
Theideaofafishbeingabletogenerateelectricitystrongenoughtolight
Theideaofafishbeingabletogenerateelectricitystrongenoughtolight
Theideaofafishbeingabletogenerateelectricitystrongenoughtolight
______enoughtimeandmoney,theresearcherswouldhavebeenabletodiscovermo
Accordingtothesurveydoneamongthelocalresidents,______enoughmoney,the
Itissimpleenoughtosaythatsincebookshaveclasses—fiction,biography,poe
______enoughtimeandmoney,theresearcherswouldhavebeenabletodiscovermo
______enoughtimeandmoney,theresearcherswouldhavebeenabletodiscovermo
随机试题
CardinalMezzofantiofBolognawasasecularsaint.Thoughheneverperforme
关于冷水(热泵)机组,正确的是()。A.采用高温工况冷水机组作为冷源,可实现
传染性非典型肺炎的病原学特点是A:细菌感染 B:衣原体感染 C:支原体感染
能作翻转运动的病原体是A.霍乱弧菌B.支原体C.立克次体D.螺旋体E.衣原体
放线菌属的生物学特性是A.革兰氏染色阳性B.无抗酸性C.在患者病灶和脓汁中可找到
Theeconomycontinuedtoexhibitsignso
学生王林因不守纪律,又一次被带进办公室,当即受到班主任的训斥:“你又违反纪律了?
生产性岗位纵向分级的步骤包括()。A.选择岗位评价要素 B.建立岗位要素
对高强度螺栓连接副终拧扭矩的施工质量检测,应在终拧( )之后、( )之内完成。A
某电厂为220kV送出,220kV单相短路电流最大,为46.449kA,此时入地
最新回复
(
0
)