Is the heart an involuntary muscle?

The human heart consists of three types of muscle tissues:

- Cardiac muscle: Cardiac muscle is the primary muscular component of the heart. It is involuntary, meaning its contractions occur automatically without conscious control. The rhythmic contraction and relaxation of cardiac muscle tissue are responsible for the pumping action of the heart, which propels blood throughout the body.

- Smooth muscle: Smooth muscle is found in the walls of the heart's blood vessels. It is also involuntary, controlling the diameter of these vessels and regulating blood flow to different tissues.

- Skeletal muscle: Skeletal muscle is not present in the heart itself. It is the voluntary muscle tissue attached to the heart's structure and involved in external movements such as skeletal muscle contractions.

Therefore, the statement "the heart is an involuntary muscle" is accurate, referring to the cardiac muscle that constitutes the majority of the heart's muscular tissue.