Question

Describe the structure of the spinal cord.

Answer 1

The spinal cord is a cylindrical structure lying in the neural canal of the vertebral column. It is also covered by meninges. It extends from the lower end of the medulla oblongata to the first lumbar vertebra. The posterior-most region of the spinal cord tapers into a thin fibrous thread-like structure called Filum terminate.

Internally, the spinal cord contains a cerebrospinal fluid-filled cavity, known as the central canal. The grey matter of the spinal cord is ‘H’ shaped. The upper end of the letter, ‘H’ forms posterior horns and the lower end forms anterior horns. A bundle of fibres passes into the posterior horn forming the dorsal or afferent root. Fibres pass outward, from the anterior horn forming the ventral or efferent root. These two roots join to form spinal nerves. The white matter is external and has a bundle of nerve tracts. The spinal cord conducts sensory and motor impulses to and from the brain. It controls the reflex actions of the body.