Spinal Cord

Central canal

White matter

Region composed mainly of myelinated axons that relay impulses to and
from the brain
and spinal cord as well as from one side of the spinal cord
to the other

Dorsal or posterior horn of spinal cord

Gray matter,
contain association neurons/interneurons

Ventral or anterior horns of spinal cord

Cell bodies of motor neurons
of the somatic nervous system

Pia mater

A delicate vascular connective tissue membrane that clings to the surface of the spinal cord; “Soft Mother”.

Arachnoid mater

Middle meningeal layer, cobweb-like

Dura mater

A double layered membrane that is the most superficial of the menineal membranes surrounding the spinal cord; “Hard Mother”.

Ventral root
of spinal cord

Axons of motor neurons of somatic nervous system

Dorsal root
of spinal cord

Sensory neuron fibers that enter spinal cord

Spinal nerve

Where dorsal and ventral roots fuse. Has both motor and sensory components and is considered to be part of the peripheral nervous system. One of 31 pairs of mixed nerves that branch from the spinal cord, emerging at various levels along its length.

Dorsal root ganglion

Cell bodies of sensory neurons