Muscular System

By Kal Edmundson


The muscle system is responsible for the movement of the body, and the system has about 700 named muscles. The muscle system also takes up about half of the human body weight. Muscle is found all throughout the body in the digestive system, inside the heart, and in blood vessels. The muscles help move things all around the body. Each of these muscles is a discrete organ constructed of skeletal muscle tissue, blood vessels, and nerves. Some of the most important muscles are the biceps, triceps, quadriceps, and pectorals.

Skeletal muscles

The skeletal muscles creates movement in the body. There are more than 600 skeletal muscles, and they makes up about 40 percent of a person’s weight. When the nervous system signals the muscle to contract, groups of muscles work together to move the skeleton. Each skeletal muscle is composed of many units called muscle fascicles. The fascicles are bound together by a type of connective tissue called fascia. (fascia is a layer of fibrous tissue)

Skeletal Muscles

Cardiac Muscles

Cardiac muscles are the muscles of the heart. They are self-contracting, automatically regulated and must continue to contract in rhythmic fashion for the whole life of the organism. The cells are Y shaped and are shorter and wider than skeletal muscle cells. Some of the cardiac muscle cells are auto-rhythmic, i.e they contract even in the absence of neuronal innervation (known as pacemaker cells).

Neural Innervation means to supply an organ or a body part with nerves or to stimulate a nerve, muscle, or body part to action.

Cardiac Muscles

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