2. 讲大脑分泌一种神马物质能够binding到一个神马细胞之类的东西上，binding多了人就会weakness，然后就想睡觉，说睡完了就binding少了，然后有人就说什么binding是sleep的原因，问支持？
GWD25-Q36 重心：清醒时不断累积，睡觉时逐渐减少。结论：adenosine累积引起睡眠
The chemical adenosine is released by brain cells when those cells are active. Adenosine then binds to more and more sites on cells in certain areas of the brain, as the total amount released gradually increases during wakefulness. During sleep, the number of sites to which adenosine is bound decreases. Some researchers have hypothesized that it is the cumulative binding of adenosine to a large number of sites that causes the onset of sleep.
Which of the following, if true, provides the most support for the researchers’ hypothesis?
如果要支持的话，就是如果这些SITES形不成，就无法导致睡眠，从而无法导致睡眠的形成，也就从反面支持了这个假设
A. Even after long periods of sleep when adenosine is at its lowest concentration in the brain, the number of brain cells bound with adenosine remains very large.睡觉时间长脑细胞和adenosine的结合还是大。
B. Caffeine, which has the effect of making people remain wakeful, is known to interfere with the binding of adenosine to sites on brain cells.咖啡因阻止adenosine累积，让人清醒。说明adenosine累积让人睡觉。支持结论。
C. Besides binding to sites in the brain, adenosine is known to be involved in biochemical reactions throughout the body. Adenosine的其他作用。无关
D. Some areas of the brain that are relatively inactive nonetheless release some adenosine. 大脑活性低的地方。。无关
E. Stress resulting from a dangerous situation can preserve wakefulness even when brain levels of bound adenosine are high. 压力。。无关
