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प्रश्न
Describe T.S. of the spinal cord.
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उत्तर
T.S. of the spinal cord shows the following features:
- The spinal cord is externally covered by the three meninges (dura mater, arachnoid mater, and pia mater). It is cylindrical but dorsoventrally flattened.
- It shows deep ventral fissure and shallow dorsal fissure. From the dorsal fissure, there extends a thin sheet of connective tissue called the dorsal septum which extends inward.
- It shows a central space called the central canal. The central canal is continuous with the 4th ventricle of the brain and contains cerebrospinal fluid. The central canal is lined by a single layer of ependymal cells. The central canal is surrounded by inner, grey matter containing cytons or cell bodies of neurons.
- Two dorsolateral horns and two ventrolateral horns give an ‘H’-shaped appearance to the grey matter. Dorsal horns extend in dorsal roots, while ventral horns extend in ventral roots of spinal nerves. Grey matter is surrounded by the white matter which divides into three columns or funiculi on either side. These are dorsal funiculi, lateral funiculi and ventral funiculi.
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संबंधित प्रश्न
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