anatomical structures, which consist of muscle tissue - a muscle man.Thanks to them, a person can move in space, the work of the heart and the rest of the internal organs.The content of the muscle tissue in the female body - 28-32%.In men, the rate is slightly higher and reaches 45%.
are three types of muscle tissue:
- skeletal,
- smooth,
- heart.
Skeletal muscle consists of striated fibers collected in bundles.Inside, they are yarns composed of proteins, thanks to which the basic function - reduction.
Cardiac muscle tissue has a structure similar to the striated fibers.They are intertwined in some areas.With this particular heart muscle is capable of rapid decline.
smooth muscles in the walls of a person represented by all the internal organs.Data reduction is a slow muscle fibers.
human skeletal muscle have a good nerve and blood supply.Each muscle bundles suitable nerves, blood vessels.They have a shell which is represented by connective tissue.Nerves that are suited to the muscles, contain the motor and sensory neurons.The first transmit impulses from the spinal cord, resulting in muscle fibers contract.Thus, the muscles in the body makes this reflex.On the pulses coming from the spinal cord it affects the brain.Therefore, actions are arbitrary.With the reduction of muscle force to move different parts of the body, which causes movement of the body and the preservation of a certain man poses.This effect is achieved through the joint and coordinated work of the extensor and flexor muscles that perform contrary actions.
Muscle man perform mechanical work.They are reduced and thus the effect on bone as a lever.Any movement requires a large amount of energy.Its sources include disintegration and the subsequent oxidation of the organic matter (fats, carbohydrates, nucleic acids).Organic substances in the muscle reacted, which must participate oxygen.
With prolonged use muscle performance gradually decreases.This condition is called fatigue.After relaxing the muscle tissue's ability to work is fully restored.
basic human muscles perform functions specific only to them.To those include:
- neck muscles.They provide the tilt and rotation of the head, hold it in a physiological position;
- trapezoid.It brings the spine to the shoulder blades, raises the shoulder girdle;
- deltoid.The main function is the movement of the upper limb backward, forward, in the direction of retraction;
- biceps (biceps).Responsible for bending arms at the shoulder joint;
-trehglavaya shoulder muscle.Performs movements of the arms back, pressing them to the body, extension arms;
- the muscles of the forearm.They are divided into flexors and extensors, which respectively carry extension and flexion of the hands and fingers.Also there are insoles and pronator, which carry radial movement of the bones;
- pectoralis major exercise to bring the hands to the body, lowers elevated shoulder raises ribs;
- obliques rotate the body to the side, while reducing pull the chest down, flex the spine, the pelvis is raised when fixing the chest;
- the rectus abdominis.By flexing the spine it is carried out;
- latissimus dorsi.For it is carried out by lowering the arms.Also, pulling her back, rotates inside;
- gluteus maximus.Performs rotation and extension of the hip outwards.Fixes Erect trunk;
- rear thigh muscles.Bending the legs in the knee joint is impossible to imagine without the normal functioning of the muscles;
- quadriceps.Unbend legs at the knee joint only at the expense of its work;
- tibial muscle.It participates in the extension of the foot, thus raising its medial border.
Muscle man is an important organ of the human body, through which are carried out not only all human movement, and coordinated work of all internal organs.
