Muscle are the active part of the m

Muscle are the active part of the motor apparatus: their contractions are producing various movements, when they are active. Functionally all muscles are divided into two groups: voluntary and involuntary muscles.
Voluntary muscles consist of striated muscle tissue and contract by the will of the man. This group includes all the muscles of head, trunk and extremities, i.e., the skeletal muscles, as well as those of some internal organs (tongue, larynx, etc.). The skeletal muscles are the organs of the muscular system. There are more than 400 skeletal muscles in the human organism: in adults they make up about two-fifths of the total body weight. Each skeletal muscle has an arterial, venous, lymphatic and nervous supply. Muscles must always act in groups.
Skeletal muscles are complex in structure. They consist of muscle fibers of different length (up to 12 cm); the fibers are usually parallel to each other and are united in bundles. Each muscle is composed of many such bundles. There are tendons at the ends of muscles by means of which they are attached to bones.
Smooth muscles form the muscular coat of internal organs such as esophagus, stomach and intestines, bladder, uterus and so on. They also form a part of the capsule and the trabeculae of the spleen; they are present single or as little cylindrical bundles of cells in the skin. They also help to form the walls of arteries, veins and some of the larger lymphatics. Smooth muscles are not richly supplied with blood vessels, as are striated muscles. A smooth muscle is capable of spontaneous contraction and can contract in two ways. Firstly, individual cells may contract completely and secondly, a wave of contractions may pass from one end of the muscle to another. Smooth muscle cells are usually elongated cells. In the skin and intestines they are long and thin, but in the arteries they are short and thick. They vary in length from12-15 mm in small blood vessels to 0,5 mm in the human uterus but their average length in an organ such as the intestine is about 200 m.
Striated muscle tissue is made up of large fibers grouped into bundles. Striated muscles are organized for the purpose of quick contraction. Such muscles are most necessary for manipulating the bones of the skeleton. Those are the muscles involved in walking, running, in turning the head and so on. Because they are so involved with the skeleton, striated muscles are sometimes called skeletal muscles. This type of muscle tissue includes the large muscle masses of the body, the muscles of the arms, legs, back etc. It includes all those muscles which must react quickly to changes in the environment, i.e. those that must be activated through an effort of will. For this reason, striated muscles are also called voluntary muscles.
Today the man has many sources of energy. Muscular energy is no longer as important in industry as it used to be, but nevertheless it remains the subject of much study. In fact, its use in sport of all kinds is looked upon as essential for good health, and its proper functioning is very important for the health of the other organs as well.

Результаты (русский) 1:

Мышцы являются активной частью двигательного аппарата: их сужений производят различные движения, когда они активны. Функционально все мышцы разделены на две группы: добровольного и недобровольного мышц.Добровольные мышцы состоят из поперечно-полосатых мышечной ткани и контракта по воле человека. Эта группа включает все мышцы головы, туловища и конечностей, т. е., скелетных мышц, а также те из некоторых внутренних органов (язык, гортань, и др.). Скелетные мышцы являются органами мышечной системы. Есть более чем 400 скелетных мышц в организме человека: у взрослых, они составляют около двух пятых общего веса тела. Каждая Скелетная мышца имеет артериальной, венозной, лимфатической и нервной питания. Мышцы должны всегда действовать в группах.Скелетные мышцы являются сложными в структуре. Они состоят из мышечных волокон различной длины (до 12 см); волокна обычно параллельно друг с другом и объединены в снопы. Каждая мышца состоит из многих таких пакетов. Есть сухожилия на концах мышц, с помощью которых они прикреплены к кости.Smooth muscles form the muscular coat of internal organs such as esophagus, stomach and intestines, bladder, uterus and so on. They also form a part of the capsule and the trabeculae of the spleen; they are present single or as little cylindrical bundles of cells in the skin. They also help to form the walls of arteries, veins and some of the larger lymphatics. Smooth muscles are not richly supplied with blood vessels, as are striated muscles. A smooth muscle is capable of spontaneous contraction and can contract in two ways. Firstly, individual cells may contract completely and secondly, a wave of contractions may pass from one end of the muscle to another. Smooth muscle cells are usually elongated cells. In the skin and intestines they are long and thin, but in the arteries they are short and thick. They vary in length from12-15 mm in small blood vessels to 0,5 mm in the human uterus but their average length in an organ such as the intestine is about 200 m.Striated muscle tissue is made up of large fibers grouped into bundles. Striated muscles are organized for the purpose of quick contraction. Such muscles are most necessary for manipulating the bones of the skeleton. Those are the muscles involved in walking, running, in turning the head and so on. Because they are so involved with the skeleton, striated muscles are sometimes called skeletal muscles. This type of muscle tissue includes the large muscle masses of the body, the muscles of the arms, legs, back etc. It includes all those muscles which must react quickly to changes in the environment, i.e. those that must be activated through an effort of will. For this reason, striated muscles are also called voluntary muscles.Today the man has many sources of energy. Muscular energy is no longer as important in industry as it used to be, but nevertheless it remains the subject of much study. In fact, its use in sport of all kinds is looked upon as essential for good health, and its proper functioning is very important for the health of the other organs as well.