PSAT Reading Question 487: Answer and Explanation

Question: 487

The process whereby caffeine works, according to Passage 1, is best paraphrased as

• A. caffeine tricks the body into thinking it has not used as much energy as it in fact has.
• B. caffeine causes the release of adenosine, stimulating the central nervous system.
• C. caffeine strongly hinders the body's ability to produce adenosine, resulting in greater alertness.
• D. caffeine helps the body generate more adenosine triphosphate storage, creating greater stores of energy.

Correct Answer: A

Explanation:

(A) In paragraph 3, the author talks about how the body knows to sleep when a large amount of adenosine is sensed by receptors in the neurons. In the last paragraph, the author says that caffeine (because it has a very similar structure to adenine) can interact with these receptors, tricking the body into thinking less adenosine is present than really is. This corresponds to choice (A), because energy consumption in the body corresponds to conversion of adenosine triphosphate into adenosine. Choices (B), (C), and (D) aren't supported anywhere in the passage.