The muscular system consists of muscle and nervous tissue controlled by the central nervous system. Human body consists of over 650 muscles comprising up to roughly % 50 of a human body's weight.
Muscle contraction fulfills the movement of the body. Muscles are attached to bones or internal organs like heart, digestive organs and blood vessels. With muscle tissue, the organs like heart, stomach can perform their functions. Body temperature is also maintained by muscle contraction.
Muscles are categorized as involuntary, voluntary and cardiac muscle.
For involuntary muscles, the terms like 'smooth muscle' because of its smooth appearance and 'visceral muscle' are also used. This kind of muscles are controlled by somatic and branchial motor nerves. Organs like the stomach, intestines, and blood vessels are controlled by the involuntary muscles to push substances through the organs. Two bones are attached by skeletal muscles through tendons.Voluntary muscles are also known as skeletal muscles. The desired movements like walking, jumping, speaking, laughing are performed with voluntary muscles which are controlled consciously by visceral motor nerves. These muscles are more strong and vulnerable to stress than other kinds.Cardiac muscles are involuntary muscles located in the heart. Pumping blood throughout the body and the heart beating are fullfilled by these muscles. Visceral motor nerves control them. It consistes of protein fibers and striations making it more strong than other involuntary muscles. Cardiac muscle cells are vulnerable to high blood pressure and they function as a unit because of their tight connection.