Answer
Labels for Nervous System Diagram:
a. Central,canal of the spinal cord (SC).
b. Gray matter of spinal cord
c. White matter of spinal cord
d. Interneuron
e. Sensory neuron cell body
Work Step by Step
In adults the spinal cord extends from the foramen magnum to the border of the first lumbar vertebra (L1).
There is a central canal in the middle of the cord ; it is filled with cererbro-spinal fluid. Spinal nerves are pairs of mixed peripheral nerves that connect with the spinal cord through foramina between the vertebrae.
Seen in cross section the centrally located gray matter displays in the shape of an H/a butterfly. Gray matter is composed of neuroglia, neuron cell bodies, and unmyelinated nerves ( axons).
White matter of the SC is peripheral to the gray matter. The latter is composed of ascending and descending tracts of whitish myelinated nerve fibers.
Spinal interneurons are found mostly in the gray matter. They transmit signals between sensory and motor neurons, and are involved in neural signal integration.
The dorsal root lies outside the spinal cord proper but sends sensory axons into the gray matter. Clusters of cell bodies of these neurons form dorsal root ganglia.
