题目内容
What is NOT correct on Microsoft's rebuttal according to the passage？
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To reset a person's biological dock, the most effective way is the use of______.
A．The pictures taken by instamatic cameras are not true.B．Photographers may not be pro
No clock is perfect, however. When organisms are deprived of the hints the world normally provides, they display a characteristic "free-running" period of not quite 24 hours. As a result, free-running animals drift slowly out of phase with the natural world. In experiments in which people are isolated for long periods of time, they continue to eat and sleep on regular, but increasingly out-of-phase. Such drift does not take place under normal circumstances, because external hints reset the clocks each day.
Light, particularly bright fight, is believed to be the most powerful synchronizer of circadian rhythms. Recent studies on humans have shown that the amount of artificial indoor fight to which people are exposed per day can resynchronize the body's cycle of sleep and wakefulness. People can inadvertently reset their body clocks to an undesired cycle by such activities as shielding morning fight with shades and heavy curtains or by reading in bed at night by bright lamp fight. Many organisms also make use of rhythmic variations in temperature or other sensory inputs to readjust their internal timers. When a clock's error becomes large, complete resetting sometimes requires days. This phenomenon is well known to long-distance air travelers as jet lag.
Apparently, biological clocks can exist in every cell and even in different parts of a cell. Hence, an isolated piece of tissue removed from an organism—for example, the eye of a sea slug—will maintain its own daily rhythm but will quickly adopt that of the whole organism when restored to it.
In the brains of most animals, a master clock appears to exist that communicates its timing signals chemically to the rest of the organism. For example, a brain removed from a moth pupa and exposed to an artificial sunrise of one time zone, then implanted into the abdomen of a headless pupa on a different time zone schedule, will cause the second pupa to emerge at the time of day appropriate to the disconnected brain floating in its abdomen. The clock in the brain triggers the release of a hormone that switches on all the complex behavior. involved in pupa emergence. In hamsters, experiments have shown a master biological clock to be located in the hypothalamus.
Scientists believe that the biological clock in humans is located in the hypothalamus, the part of the brain that regulates such basic drives as hunger, thirst, and sexual desire. The biological clock itself is believed to be a cluster of nerve cells called the suprachiasmatic nucleus.
Biological docks cannot be found in______.
A．Malocclusion.B．Stress.C．Smoking.D．Caffeine.
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