Skeletal muscle is what most people think of as muscle. Skeletal muscle is responsible for controlling body movement, maintaining body posture, and generating heat in the body. Skeletal muscle gets its name from the fact that it is attached to bone.
Skeletal muscle is a striated, or striped, muscle. These striations are the result of long, parallel muscle fibers making up the muscle. Skeletal muscle is connected to bones via tendons. Skeletal muscles are responsible for all body movements from sitting, standing and walking, to smiling and laughing. Skeletal muscles are voluntary muscles, meaning they are under our conscious control through the somatic nervous system.
Smooth muscle is found in the walls of hollow internal structures such as blood vessels, the esophagus, stomach, small intestine, large intestine, and urinary bladder. Smooth muscles, as the name implies, is smooth not striated. Smooth muscles are involuntary muscles, meaning they are not under our conscious control. They are controlled by the autonomic nervous system.
Cardiac muscle makes up most of the wall structure of the heart. It is found only in the heart. Cardiac muscle is striated or striped with light and dark bands similar to skeletal muscle. Unlike skeletal muscle, cardiac muscle is involuntary muscle, not under our conscious control. It is controlled by an internal pacemaker and the autonomic nervous system.