Nervous tissue is part of the central nervous system as well as the peripheral nervous system. The tissue can be comprised of two cell types: neurons and neuroglia, both of which perform slightly different functions in how the body transmits nerve impulses.
Neurons react to stimuli, when the neurons are stimulated the neurons generate and transmit a nerve impulse. This neuron is able to generate and pass this impulse due to its structure. It is comprised of a axon, a cell body and dendrites. the impulse passes on through the different types of neurons: motor, sensory and relay which will bring the impulse to an effector which will react in the appropriate way to the stimuli.
Neuroglia are often referred as non-nervous cells as they aid impulses to pass throughout the body but do not themselves generate the nerve impulses. There are many different cell types of the neuroglia as there are many different functions they need to be able to carry out:
- Astrocyte- They provide the nutrient demands of the neurons.
- Ependymal- They make up the cerebrospinal fluid, as well as lining the brain.
- Microglial- They provide protection against foreign cells and debris in the central nervous system.
- Oligodendrocyte- They have a structural function of insulating cells and make up the myelin sheath which allows the impulses to pass quicker throughout the body
- Schwann Cell- Similar to oligodendrocytes as they make up the myelin sheath and are found in the peripheral nervous system which differs from the oligodendrocytes.