A Certain Drug Decreases Heart Rate by Blocking a Receptor

question 5

Multiple Choice

A certain drug decreases heart rate by blocking a receptor on cardiac pacemaker cells. This drug probably binds to ________ receptors.

• A) nicotinic cholinergic
• B) muscarinic cholinergic
• C) alpha-1 adrenergic
• D) alpha-2 adrenergic
• E) beta-1 adrenergic

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Definitions:

Hormones

Chemical messengers produced by the endocrine glands that regulate various bodily functions and processes.

Circadian Rhythm

The natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours.

Mates

Refers to individuals chosen as partners for reproduction or companionship, typically within the context of romantic or sexual relationships.

Evolutionary Psychologists

Scientists who study the psychological traits such as memory, perception, and language from a modern evolutionary perspective.