A Drug Decreases Heart Rate by Blocking a Receptor on Cardiac

question 53

Multiple Choice

A drug decreases heart rate by blocking a receptor on cardiac muscle cells.This drug probably binds to:

• A)a₁ receptors.
• B)fi₂ receptors.
• C)fi₁ receptors.
• D)nicotinic cholinergic receptors.

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Definitions:

Cylindrical

Relating to the surface or shape of a cylinder, which is a solid geometric figure with straight parallel sides and a circular or oval cross section.

Spherical

Having the shape of a sphere; relating to or resembling a ball or globe.

Antifriction Bearings

Bearings designed to reduce friction between moving parts while supporting radial and axial loads, often using balls or rollers.

Bearing

A machine element that constrains relative motion to only the desired motion, reducing friction between moving parts.