How To Lose Belly Fat Fast

If you know lots of things about muscles, you can do right things and avoid from doing wrong things which may cause wasting time.

Under the microscope, threadlike and cylindrical skeletal muscle cells appear in bundles. They are characterized by many crosswise stripes and mul­tiple nuclei. Each fine thread is a muscle cell or, as it is usually called, a muscle fiber. This type of muscle tissue has three names: skeletal muscle, because it attaches to bone; striated muscle, because of its cross stripes or striations; and volun­tary muscle, because its contractions can be con­trolled voluntarily.

In addition to skeletal muscle, the body also contains two other kinds of muscle tissue: cardiac muscle and nonstriated, smooth, or involuntary muscle. Cardiac muscle composes the bulk of the heart. Cells in this type of muscle are also cylindri­cal, branch frequently, and then re­combine into a continuous mass of interconnected tissue. Like skeletal muscle cells, they have cross striations. They also have unique dark bands called intercalated disks where the plasma mem­branes of adjacent cardiac fibers come in contact with each other. Cardiac muscle tissue demon­strates the principle that “form follows function.” The interconnected nature of cardiac muscle fibers helps the tissue to contract as a unit and increases the efficiency of the heart muscle in pumping blood.

Nonstriated or smooth muscle cells are tapered at each end, have a single nucleus, and lack the cross stripes or striations of skeletal muscle cells. They have a smooth, even appear­ance when viewed through a microscope. They are called involuntary because we normally do not have control over their contractions. Smooth or in­voluntary muscle forms an important part of blood vessel walls and of many hollow internal organs (viscera) such as the gut, urethra, and ureters. Because of its location in many visceral structures, it is sometimes called visceral muscle. Although we cannot willfully control the action of smooth muscle, its contractions are highly regu­lated so that, for example, food is passed through the digestive tract or urine is pushed through the ureters into the bladder.

Muscle cells specialize in contraction, or short­ening. Every movement we make is produced by contractions of skeletal muscle cells. Contractions of cardiac muscle cells keep the blood circulating, and smooth muscle contractions do many things; for instance, they move food into and through the stomach and intestines and make a major contribution to the maintenance of normal blood pressure.

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