Question

describe the major functions of the three types of muscles.

Explanation:

Skeletal muscle is attached to bones. Its contractions are under conscious control (voluntary), enabling body movements like walking, running, etc. It also helps in maintaining posture (e.g., keeping the body upright when sitting or standing) and generates heat (important for maintaining body temperature).
Smooth muscle is found in the walls of internal organs (e.g., stomach, intestines, blood vessels). Its contractions are involuntary (not under conscious control). In the digestive system, it helps in peristalsis (wave - like movements that push food along the digestive tract). In blood vessels, it can constrict or dilate to regulate blood flow.
Cardiac muscle is only in the heart. Its rhythmic, involuntary contractions (heartbeats) pump blood throughout the body, ensuring the delivery of oxygen and nutrients to cells and the removal of waste products.

Answer:

Skeletal muscle: Voluntary movement, posture maintenance, heat production.
Smooth muscle: Involuntary internal organ functions (e.g., digestion, blood vessel constriction).
Cardiac muscle: Heart contraction for blood pumping.