Neuroglia – The Army of The Nervous System
Have you ever heard the saying,
Behind every successful man is an even more successful wife?
The same concept applies to neuroglia:
- Glial cells are the unsung heroes without which neurons would be totally useless and unable to survive.
Neuroglia: Function and Definition
First, let’s make things clear:
Three different names referring to the same type of cell. (I used to be quite confused until I finally realized that these are three names referring to the same object–as if there weren’t enough words to remember in neuroanatomy as it is…)
2. Poison Defense: Some glial cells support the role of “blood brain barrier.” They will simply block most harmful substances from ever reaching the neuron. (Without this barrier, most molecules in the blood would become deadly poisons!)
3. Support electrical communication:
a. Ion concentration regulator: Neuroglia regulate the amount of ions around the neurons. As such they make sure that the neurons environment is optimal for the transmission of the electric pulse. (Learn more about electric signal conduction)
b. Myelin Sheath creation: Some glia are responsible for creating and repairing the myelin sheath around the axon of the neuron. The myelin sheath is what ensures fast / salutatory propagation of the electric signal) (Oligodendrocyte and Schwann cells)
4. EMT services: Some neuroglia proliferate and rush to a site of injury within the central nervous system. (Microglia)
Types of Neuroglia
Are you ready to absorb even more vocab? Here we go!
In the Central Nervous System (~in the brain)
Macroglia are divided into two sub-categories: The Astrocytes and the Oligodendrocytes.
As the prefix implies – Astro means star, astrocytes look like stars with lots of branches (look similar to dendrites – but they are NOT dendrites!)
Astrocytes have two sub-categories themselves:
a. Protoplasmic astrocytes
They are found in the gray matter
b. Fibrous astrocytes – They are found in the while matter.
Oligodendrocytes have 3 sub-categories (I told you this would be tough – I’ll try to make it short!):
a. Satellite oligodendrocyte – Myelin sheath creation
b. Interfascicular oligodendrocyte – They are found in between axons (“inter”) and can “myelinate” more than one axon at a time.
c. Vascular oligodendrocyte – They are found close to small capillaries.
These are the smallest types of glia (they are micro!) This small size is what allows them to proliferate around a site of injury in the CNS
They are involved in neuronal development.
- Mnemonic for the CNS: “Mark And Peter Found Online Some Indian Veal – Micro Epic.”
We’re almost finished! We only have two types of neuroglia left in the Peripheral Nervous System (PNS).
In the Peripheral Nervous System (~spinal cord)
OK! We’re done!
Minimum to Remember About Neuroglia
- Support nutrition
- Poison Defense
- Support electrical communication
- EMT services
- And much, much more…. 🙂
Types of Neuroglia
– too many!
- Once you remember the name and what they mean you can recall 90% of what we just covered. Use the chart I prepared for you if it helps!
Mnemonic for neuroglia in the CNS: Mark And Peter Found Online Some Indian Veal – Micro Epic.
If you want more articles and videos about the Nervous System, you can find them here. More resources are available to help make Biology fun. I invite you to absorb all the content you can find here at Interactive-Biology.com.