The muscular system allows the body to move. It consists of 639 muscles and tendons which are bands of tough, inelastic fibrous tissue that connects a muscle with its bony attachment.
The muscular system is controlled by the nervous system.
Provides strength for the body
Provides balance for the body
Gives posture to the body
Allows the body to move
Provides heat for the body to keep it warm
These are the muscles of the heart. They are controlled by the autonomic nervous system. They are involuntary and can't be controlled by human thought.
These are also controlled by the autonomic muscle system and are involuntary. The intestinal muscles are smooth muscles.
Skeletal muscles are striated or "striped". They are voluntary muscles and can be controlled by conscious thought. Macles in the arms and lets are examples of skeletal muscles. A further subdivision are the extensor and flexor muscles. An extensor muscle is a muscle that works to extend or straighten a body part, effectively enlarging the angle between body parts. Examples of extensor muscles include the muscles that straighten the elbow or the knee. The opposite equivalents of extensor muscles are flexor muscles, which work to close a joint, for example to bend the arm at the elbow or the leg at the knee.