The spinal cord and its structure
The spinal cord - is part of the central nervous system. It is located in the spinal canal based on pervogof cervical vertebra and lumbar to the first organized collection of vertebrate arcs. In the spinal canal is not only the spinal cord, but also the blood vessels, adipose tissue, the meninges, cerebrospinal fluid. But what? It has a thickening at the place of exit from the nerves to the extremities, due to their innervation. This two branches- Cervical and lumbar. They contain no small number of nerve fibers, cells compared with the number of cells and fibers in other departments.
The structure of the spinal cord consists of gray matter. It is surrounded by another substance - a white substance. The entire spinal cord is divided into two halves which are symmetricand which is formed with an intermediate vertical Acquire matter where laid a center channel from the spinal fluid.
The spinal cord contains approximately 13 million. Neurons, which are divided into four main groups: motor, interneurons, associative cells and sympathetic, parasympathetic neurons. Lengthspinal cord may be about 40 to 45 cm for an adult person. From each of the 31 segments of the brain depart roots. they are divided into sensory and motor.
The morphological structure of the boundaries of the spinal cord - a longitudinal grooves and folds on its surface. The lower part of the spinal mtapers and changes brain activity in the brain cone. A major role in coordinating movements play intermediate neurons that transmit signals to motor neurons.