Which involuntary muscle tissue is found only in the heart?

Which involuntary muscle tissue is found only in the heart?

• A. Skeletal Muscle
• B. Cardiac Muscle
• C. Smooth Muscle
• D. Striated Muscle

Answer: (B)

Cardiac muscle is the tissue that is involuntary and found only in the heart. It shares the striped appearance of skeletal muscle, but its fibers are branched and bound together by intercalated discs, which enable rapid, coordinated contractions that keep a steady heartbeat. This automatic contractile capability comes from pacemaker cells that set the rhythm, so no conscious effort is needed. Skeletal muscle is voluntary and attaches to bones; smooth muscle is involuntary and lines hollow organs, not the heart. While striated muscle describes the striped appearance, that category isn’t exclusive to the heart, since skeletal muscle also shows striations.

Cardiac muscle is the tissue that is involuntary and found only in the heart. It shares the striped appearance of skeletal muscle, but its fibers are branched and bound together by intercalated discs, which enable rapid, coordinated contractions that keep a steady heartbeat. This automatic contractile capability comes from pacemaker cells that set the rhythm, so no conscious effort is needed. Skeletal muscle is voluntary and attaches to bones; smooth muscle is involuntary and lines hollow organs, not the heart. While striated muscle describes the striped appearance, that category isn’t exclusive to the heart, since skeletal muscle also shows striations.