更多"Bats are extremely shy creatures an"的相关试题:
[单项选择]Contrary to popular opinion, bats are not generally aggressive and rabid; most are shy and
A. disfigured
B. punctual
C. depraved
D. harmless
[单项选择]Bats are surprisingly long-lived creatures, some ______ a life span of around 20 years.
A. having
B. had
C. have
D. to have
[单项选择]According to the passage, bats and adult owls cannot see colours,
A. because they hunt at night
B. because they cannot see light
C. because they have no cones and rods
D. because they have no cones
[单项选择]Bats find insects in the dark of night with the help of ______.
A. echoes
B. eyesight
C. sound waves
D. none of the above
[单项选择]Why are sharks useful for humans
A. For their tasty meat.
B. For the principle of their defense system against disease.
C. For their solid skin.
D. For the principle of their birth modes.
[单项选择]Why sharks are useful for humans
A. Their tasty meat.
B. The principle of their defense system against disease.
C. Their solid skin.
D. The principle of their birth modes.
[单项选择]Bats (are able) (to guide them) by producing sound waves (too high) for us (to hear).
A. are able
B. to guide them
C. too high
D. to hear
[单项选择]
We sometimes think humans are uniquely vulnerable to anxiety, but stress seems to affect the immune defenses of lower animals too. In one experiment, for example, behavioral immunologist (免疫学家)Mark Laudenslager, at the University of Denver, gave mild electric shocks to 24 rats. Half the animals could switch off the current by turning a wheel in their enclosure, while the other half could not. The rats in the two groups were paired so that each time one rat turned the wheel it protected both itself and its helpless partner from the shock. Laudenslager found that the immune response was depressed below normal in the helpless rats but not in those that could turn off the electricity. What he has demonstrated, he believes, is that lack of control over an event, not the experience itself, is what weakens the immune system.
Other researchers agree. Jay Weiss, a psychologist at Duke University School of Medicine, has shown that animals who are allowed to control unpleasant stimu
A. try to control unpleasant stimuli
B. turn off the electricity
C. behave passively in controllable situations
D. become abnormally suspicious
