What is the contraction of smooth muscles?

Smooth muscle contraction is a type of muscle contraction that occurs in the walls of many inner structures of the body, such as blood vessels, digestive tract organs and reproductive organs. Unlike the skeletal muscles, which are located near the skin and which perform voluntary movements of the joints of the body, such as walking or lifting a fork to eat, smooth muscles perform automatic, unconscious functions such as pushing blood through arteries or spent food through the intestines. The contraction of smooth muscles differs from the continuing of the skeletal muscle in that it causes the entire wall of the vessel undulating, moving as a unit for the transport of the container content. The walls of the walls of such structures such as arteries and veins, esophagus, stomach and intestines and bladder and uterus are found, this type of muscle usually has a shape in the shape. Fusiform muscle fibers are in the shape of a spindle and while skeletal muscle fibers can also take this shape, skeletal contractions skeletal muscle occurs linearly in direction that is in parallel with DThe fiber's Él, while the contraction of smooth muscles involves expansion and contraction of muscle tissue in several directions. Therefore, the contraction of the smooth muscles creates a kind of wavy, squeezing movement known as peristaltiza that pushes blood, partially fissioned food and reproductive cells in one direction in slow waves.

This type of muscle contraction is not controlled by the central nervous system in the brain, but by an autonomic nervous system, a part of the peripheral nervous system that coordinates involuntary effects such as breathing and heart rate. Based on how muscle cells are penetrated by functional units autonomic nervous system, nerves, smooth muscle are classified into two types of muscles: unit and multiple. In the smooth muscles of one unit, one cell in the moving unit of the smooth muscles is innervated by one nerve. The nerve impulse spreads to neighboring cells in a leaf of muscle, such as the lightning thatIt hits the ground, causing collective contraction throughout the unit. The smooth muscle with smooth muscle is contracted in individual cells, where very small and gentle engine control is required, as in dilation and magnification of the iris of the eye. The vast majority of the smooth muscles of the body is one unit.

in muscle cell, molecules arranged linearly in fibers called actin and myosin provide a mechanism of contraction of smooth muscles. The formation of a series of interconnected strings, similar to stringing of chain mail, enables the contraction of several directions. Several proteins known as Calmodulin, Caldesmon and Calponin facilitate this muscle contraction by linking to calcium Ions. It is this binding action that changes the molecular structure of the smooth muscle cell and thus brings contraction.