John Reports to His Doctor That He Has Been Experiencing

question 2

Multiple Choice

John reports to his doctor that he has been experiencing changes in his appetite. This suggests that John is experiencing fluctuations in which neurotransmitter?

• A)acetylcholine
• B)histamine
• C)glutamate
• D)serotonin

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Definitions:

Isovolumetric Contraction

A phase of the cardiac cycle where the ventricles contract with no change in volume, occurring between the closure of the atrioventricular valves and the opening of the semilunar valves.

Semilunar Valves

Heart valves located at the bases of the large arteries that leave the heart; they prevent blood from flowing back into the heart.

AV Valves

The atrioventricular valves, consisting of the tricuspid and mitral valves, regulate blood flow from the atria to the ventricles in the heart.

Left Ventricle

The chamber of the heart that receives oxygen-rich blood from the left atrium and pumps it out to the body through the aorta.