The Human Body: The Muscular System

Contraction is autonomously controlled by the spinal cord and certain neurotransmitters, mainly motor neurons derived from the neurotransmitter acetylcholine (Campbell, 2012). These spontaneous strongly contracting cell bundles are multinuclear and striped (Mescher, 2013). Cardiovascular muscle is a specific muscle found in the outer layer of the heart (Paulsen, 2010). Like skeletal muscle, cardiac muscle consists of cells containing multiple nuclei.

The muscular system is one of the organ systems of the body and consists of three muscles: bone, smooth muscle and heart. Body muscles enable blood movement, posture, circulation. In vertebrates such as humans, the myocardium is completely autonomous, but the muscular system is controlled by the nervous system. Skeletal muscle is a soft tissue that most people think when thinking about the muscles of the body. It is a soft tissue that is fixed to the bone by a tendon and allows the body to move. The skeletal muscle is striped and contains a bundle of muscles, the basic unit of muscle. There are about 639 skeletal muscles in the human body.

The muscular system is a collection of all the muscles that make up the body. It is a wide range of muscles and nervous system that spread throughout the body. In general, the human body consists of about 650 muscles (Shier, Butler, Lewis, 2009). The muscular system can be divided into three kinds of muscles, myocardium, smooth muscle, and skeletal muscle (p.212). Myocardium is an unconscious muscle found only in the heart wall, especially the myocardium. Myocardium contracts automatically and tightens the heart wall rhythmically (p. 212-216). The heart beats about 100,000 times a day without interruption (page 18). Smooth muscle is an involuntary muscle found on the wall.