| Biological clocks are physiological
systems that enable organisms to live in harmony with the rhythms of nature,
such as the cycles of day and night and of the seasons. Such biological "timers"
exist for almost every kind of periodicity throughout the plant and animal
world, but most of what is known about them comes from the study of circadian,
or daily, rhythms. Circadian rhythms cue typical daily behavior patterns even in
the absence of external cues such as sunrise, demonstrating that such patterns
depend on internal timers for their periodicity. 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 is A. (A) stones B. (B) plants C. (C) animals D. (D) human beings [填空题]Fishes’ structural and physiological adaptations for life at extremes are still waiting for ______.
[单项选择]Some people assert that prosecutors should be allowed to introduce illegally obtained evidence in criminal trials if the judge and jury can be persuaded that the arresting officer was not aware of violating or did not intend to violate the law while seizing the evidence. This proposed "good-faith exception" would weaken everyone’s constitutional protection, lead to less careful police practices, and promote lying by law enforcement officers in court.
The argument above for maintaining the prohibition against illegally obtained evidence assumes that A. defendants in criminal cases should enjoy greater protection from the law than other citizens do. B. law enforcement authorities need to be encouraged to pursue criminals assiduously. C. the legal system will usually find ways to ensure that real crimes do not go unprosecuted. D. the prohibition now deters some unlawful searches and seizures. E. (E) courts should consider the motives of law enforcement officers in deciding whether evidence brought forward by the officers is admissible in a trial. [单项选择]A. Reconsider his position later. B. Allow the student to miss class.
C. Lower the student’s grade. D. Suggest that the student try to reschedule the operation [单项选择]
Evolutionary theories. The Belgian George Lemaitre proposed the idea that about 20,000 million years ago all the matter in the universe—enough, he estimated, to make up a hundred thousand million galaxies—was all concentrated in one small mass, which he called the" primeval atom". This primeval atom exploded for some reasons, sending its matter out in all directions, and as the expansion slowed down, a steady state resulted, at which time the galaxies formed. Something then upset the balance and the universe started expanding again, and this is the state in which the universe is now. There are variations on this theory: it may be that there was no steady state. However, Basically, evolutionary theories take it that the universe was formed in one place at one point in time and has been expanding ever since. 我来回答: 提交
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