Skeletal muscle

Skeletal Muscle

A cross section of skeletal muscle.

Skeletal muscle is a type of muscle tissue that is attached to the skeleton. It is responsible for voluntary movements of the body, and is one of three major muscle types, the others being cardiac muscle and smooth muscle.

Structure

Skeletal muscle fibers are long, cylindrical cells that contain multiple nuclei. They are composed of myofibrils, which are made up of sarcomeres, the basic unit of muscle contraction. Each sarcomere is composed of long, fibrous proteins that slide past each other when the muscles contract and relax.

Function

Skeletal muscles are responsible for all voluntary movements of the body. They work in pairs to move limbs and provide the force needed for bodily functions such as breathing and swallowing. Skeletal muscles also help maintain body temperature by producing heat during physical activity.

Clinical significance

Diseases of the skeletal muscle can lead to weakness, fatigue, and loss of mobility. These include muscular dystrophy, myasthenia gravis, and rhabdomyolysis. Treatment for these conditions may include physical therapy, medication, and in some cases, surgery.

See also

• Muscle contraction
• Muscle tissue
• Myofibril
• Sarcomere