Which cells characterize the conduction system as non-contractile yet conductive?

Which cells characterize the conduction system as non-contractile yet conductive?

• A. Specialized non-contractile impulse-conducting cells.
• B. Contractile cardiomyocytes.
• C. Neural crest cells.
• D. Smooth muscle cells.

Answer: (A)

The main idea is that the heart’s conduction system uses specialized non-contractile impulse-conducting cells. These cells are built to generate and rapidly propagate electrical signals, not to contract and pump blood. They form the SA node, AV node, bundle of His, and Purkinje fibers, coordinating the heartbeat by timing the spread of impulses. In contrast, contractile cardiomyocytes make the forceful contractions that move blood, so they’re designed for shortening and generating pressure rather than rapid electrical conduction. Neural crest cells and smooth muscle cells aren’t the primary components of the conduction pathway.

The main idea is that the heart’s conduction system uses specialized non-contractile impulse-conducting cells. These cells are built to generate and rapidly propagate electrical signals, not to contract and pump blood. They form the SA node, AV node, bundle of His, and Purkinje fibers, coordinating the heartbeat by timing the spread of impulses. In contrast, contractile cardiomyocytes make the forceful contractions that move blood, so they’re designed for shortening and generating pressure rather than rapid electrical conduction. Neural crest cells and smooth muscle cells aren’t the primary components of the conduction pathway.