Chitra657 wrote:
Ilishar wrote:
No doubt that Option B supports the argument but Option E also states that sleep preserves wakefulness even when the brain levels of bound adenosine are high which implies that high levels of adenosine cause the onset of sleep and stress counters it. How can we say that E is out of context?
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Even though I understand why B is correct, I had the exact same doubt about E. Could you pls explain why E is wrong?
GMATNinja VeritasKarishma Thank you in Advance!
The correct answer should support the hypothesis that "the cumulative binding of adenosine to a large number of sites... causes the onset of sleep."
Let's see how answer choice (E) affects this hypothesis.
Quote:
(E) Stress resulting from a dangerous situation can preserve wakefulness even when brain levels of bound adenosine are high.
This tells us that stress from a dangerous situation can preserve wakefulness. But what does it tell us
explicitly about adenosine? Not very much. It confirms that adenosine can bind to something in the brain, but we have no idea what effect this bound adenosine is having.
You mention that (E)
implies that "high levels of adenosine cause the onset of sleep and stress counters it." But as you say, that is only an
implication. Going by the
exact words of (E), we really don't know what effect the binding of adenosine has. Maybe it reduces stress, but has nothing to do with sleep or wakefulness? Or maybe it doesn't even affect stress?
Going by the precise words in (E), we just can't say what effect adenosine has. So (E) is incorrect.
I hope that helps!