What is the difference between voluntary and involuntary muscles?

Voluntary muscles are those that can be controlled consciously, meaning that individuals have the ability to decide when to contract or relax these muscles. This control allows for intentional movements, such as walking, running, or lifting objects. These muscles are primarily composed of skeletal muscle tissue, which is striated in appearance due to its organized structure.

Involuntary muscles, on the other hand, operate without conscious control. These muscles function autonomously to perform essential processes such as digestion, heartbeat regulation, and blood vessel constriction. The primary types of involuntary muscles are smooth muscles, found in the walls of internal organs, and cardiac muscle, which makes up the heart. These muscles are not striated and work continuously and rhythmically without the need for direct brain commands.

Thus, the distinction lies in the nature of control: voluntary muscles are consciously controlled, while involuntary muscles are not. The correct answer underscores this fundamental difference in muscle control mechanisms.