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:

Weathering

The process by which rocks and minerals break down into smaller pieces by physical, chemical, or biological means, leading to the formation of soil and sediments.

Bedrock

The solid rock underlying loose deposits such as soil or alluvium, often exposed at the Earth's surface or underlying the soil layer.

Sediment

Particles of organic or inorganic matter that accumulate in a loose, unconsolidated form, often deposited by water, wind, or ice.

Tectonic Forces

the forces generated by the movements of Earth's lithospheric plates, responsible for geological features and activities.