muscular system refers to one of the most important biological subsystems by which the body performs various movements.
It can be represented as a set of muscle fibers capable of contraction.The fibers are interconnected to beams that form as a muscle specific organs, or may themselves enter into the internal organs.Muscle mass is much higher than other organs in some animals, it is 50 percent of body weight, and in humans - 40 percent.Muscular system converts the chemical energy into heat and mechanical energy.
In vertebrate muscle musculature is divided into the following groups:
- Somatic, contains an inner forming muscles and limbs.This includes skeletal muscle.
- Visceral (part of the viscera).It is smooth and cardiac muscles.
human muscular system
Skeletal muscles are striated and arbitrary.They are attached to the bones and are cylindrical fiber length of 1-10 cm.
Each muscle fiber - is undifferentiated cytoplasm (sarcoplasm) with many nuclei located on the
muscles help to maintain body balance, to carry out the movement in space and vital movements of all parts of the body.
Smooth muscles are located in the walls of blood vessels and internal organs.The length of this type of muscle is 0.02-0.2 mm.They have no striation, their shape resembles a spindle.Smooth muscle cells are oval in the center core.
Smooth muscles help transport that is contained in hollow organs (food in the intestine, for example).They are involved in the regulation of the pressure, the expansion and contraction of the pupil, and other movements in the body.For smooth muscle meets the autonomic nervous system.
muscular system also includes heart muscle, which is only in the heart walls.She continuously declining life, providing blood flow through the vessels and feeding substances necessary tissues and organs.
The human body contains about 400 muscle striated, which are reduced under the control of the central nervous system.
Musculoskeletal system includes muscles, bones, tendons, joints, ligaments and cartilage that make up almost 75% of the weight of the person.This system gives the human body a certain shape, allows him to stand and walk.Skeleton to the organs and tissues is a bony skeleton, it also protects vital organs from damage.The bones accumulate minerals such as phosphorus and calcium.The interior of the bone marrow is represented by participating in the formation of blood cells (red cells, white cells and platelets).
injuries and diseases If any of the parts of the musculoskeletal system is disturbed statics and dynamics of the whole organism.In addition, he suffers the whole musculoskeletal system, internal organs, too, cease to function properly.For example, by shortening one of the limbs curved spine, which causes deformation of the chest, as a consequence - suffer from circulatory and respiratory organs.