Fever blisters (or cold sores) are painful sores, which occur on lips, cheeks, chin, fingers, nostrils, or even genitals. These are caused by a virus, named âherpes simplexâ. Fever blisters are contagious and are usually mistaken to be canker sores (which are actually mouth ulcers and occur inside the mouth).
The spinal ganglia or dorsal root ganglia contain the cell bodies of sensory neurons entering the cord at that region. nerve-a group of fibers (axons) outside the CNS. The spinal nerves contain the fibers of the sensory and motor neurons.A nerve does not contain cell bodies.They are located in the ganglion (sensory) or in the gray matter (motor). tract-a group of fibers inside the CNS. The spinal tracts carry information up or down the spinal cord, to or from the brain.he spinal cord is the connection center for the reflexes as well as the afferent (sensory) and efferent (motor) pathways for most of the body below the head and neck. The spinal cord begins at the brainstem and ends at about the second lumbar vertebra.
The grey matter also has a histologically visible central canal running through it. The ventral horns of the grey matter contain the cell bodies of motor neurones whilst the dorsal horns contain sensory neurons where the cell bodies are found in the dorsal root ganglia. Please see sensory pathways for further information on the composition of nerve fibres within the spinal cord.