Cardiac muscle is characterized by which features?

Cardiac muscle is indeed characterized as striated and involuntary. The term "striated" refers to the appearance of cardiac muscle fibers, which contain alternating light and dark bands (striations) due to the arrangement of actin and myosin filaments. This striated appearance is similar to that of skeletal muscle, but cardiac muscle operates under a different control mechanism.

The "involuntary" aspect means that cardiac muscle contractions are not consciously controlled; rather, they are regulated by the autonomic nervous system and intrinsic conduction system of the heart. This allows the heart to pump blood effectively without the need for conscious thought. This distinguishes cardiac muscle from skeletal muscle, which is voluntary and can be controlled consciously.

Understanding these characteristics is essential in differentiating cardiac muscle from other types of muscle tissue, such as skeletal muscle and smooth muscle, which have distinct functions and control mechanisms.