Which of the Following Seems to Be Involved in Causing

question 537

Multiple Choice

Which of the following seems to be involved in causing sleepiness?

• A) high blood levels of adenosine
• B) low blood levels of adenosine
• C) low blood levels of melatonin
• D) high blood levels of dopamine

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Definitions:

Ancient Trees

Very old trees, often centuries or millennia in age, which can provide historical and environmental insights.

Crown

In dentistry, an artificial cover for a damaged or decayed tooth; in botany, the upper part of a tree, including branches and leaves.

Phloem

A type of vascular tissue in plants that transports sugars and other metabolic products downward from the leaves.

Xylem

A type of vascular tissue in plants responsible for the transport of water and dissolved nutrients from the roots to the rest of the plant.