The spinal cord is an important structure of the Central Nervous System. It is an extension of the brain and is a rough, cylindrical; two feel long structure lying within the case of the backbone.
image source: socalpain.com
The spinal cord originates in the brainstem and runs down through the backbone and ends in the hips. In appearance, it is grey inside and white outside.
ADVERTISEMENTS:
It is connected to the peripheral nervous system through 31 pairs of spinal nerves.
The spinal cord is protected by the vertebral column, which is composed of 24 individual vertebrate of the cervical, thoracic, lumbar, the sacral and coccygeal portions.
The internal structure of the spinal cord is much simpler and more uniform throughout its various parts than is that of the brain. No matter where it is sectioned (cut), it presents the same essential appearance. The interior is grey matter (cell bodies), so distributed as 10 present the picture of a butterfly whose essential form is the letter H. Outside the grey matter are great column of white matter making up various fibre tracts passing up and down the cord. Dividing the cord into symmetrical halves are two median clefts, the dorsal and ventral fissures. Between them, in the central parts of the cord, are the two commissars joining the two halves of the cord.
Functions of the Spinal Cord:
The spinal cord performs the following important functions:
ADVERTISEMENTS:
It connects the lower parts of the brain with the sensory and motor nerves from the body.
Nerves from the sense receptors for heat, cold, pain, pressure and muscular activity go to the spinal cord.
It is responsible for behaviour known as reflex actions. A reflex action is an automatic, involuntary response triggered by a stimulus. It mediates complex reflex actions like blinking, knee-jerk, sneezing, coughing, etc. Damage to the spinal cord leads to paralysis.