[libribook.com] Traumatic Scar Tissue Management 1st Edition

Neurons
• Excitable nerve cells and their processes (dendrites and axons), which transmit
information in the form of electrical signals to other neurons and other cells of
the body (Fig. 4.3).
• Sensory neurons provide information about the body’s internal and external
environment.
• Motor neurons assist with reaction or response to the environment.
• Interneurons form connections between neurons and function as a relay station;
for example, in the spinal cord a fast-track connection between a sensory and
motor neuron creates a reflex arc which speeds reaction time as it cuts out the
middle man … the brain.
Neuroglia (glia)
• Specialized connective tissue cells
• Ensure the health of neurons and support their function (e.g. create the blood–
brain barrier, marshal immune responses, transport of nutrients, clean up
debris, help secure neurons in place and produce myelin).
In addition to the two main cells, the CNS comprises extracellular matrix
(ECM), gray and white matter. ECM within the CNS is histologically similar to
the presentation outlined in Chapter 2.
CNS gray matter comprises the cell bodies, neuronal dendrites and axons and
synapses between neurons. Synapses facilitate communication between neurons
and other tissues. Neuronal dendrites are covered with synapse terminations that
communicate with the terminations of adjacent axons. Each neuron can
communicate with roughly 10 000 other neurons. Some axons can synapse
directly onto: