Question

5. List the 6 Neuroglia cells located in the nervous system and describe their general structure, function, and location. (10 points) 6. Describe the Myelin sheath and tell me why it is important? (3 points)

Answer 1

The 6 neuroglia cells located in the nervous system are -

a) Astrocytes - These are star-shaped glial cells that are found in the (CNS)Central Nervous System(brain). Their main functions are to provide protection and support to the neurons, to exchange nutrients and other important chemicals, regulation of energy metabolism, detoxification and reaction to injury.

b) Oligodendrocytes- These are the types of glial cells thatcontain small amount of cytoplasm surrounding a rounded-nuclei. They are also found in the CNS. They provide insulation and support to the axons of the CNS.

c) Ependymal cells- These glia cells are found lining the empty cavities known as ventricles in the brain. Their main function is to filter out certain materials out of the blood vessels to form CSF( cerebrospinal fluid) and then utilizing their cilia to circulate it through the empty vesicles and to the remaining part of the CNS.

d) Microglia- These glial cells act as immune system of the CNS. Just like macrophages, these cells mediate immune responses by removing dead neurons by phagocytosis.

e) Satellite cells- These cells cover the surface of the nerve cell bodies in sympathetic, parasympathetic and sensory ganglia. They help in supplying nutrients to the surrounding neurons and also act as cushions to protect the cells.

f) Schwann cells- These cells are found wrapping themselves around the axons of neurons in the Peripheral Nervous System(PNS). These cells helps in forming a protective layer known as the myelin sheath. The myelin sheath helps in undisrupted transmission of electrical impulses from one neuron to the next neuron.

Ans- 6) Myelin sheath is an insulating layer formed around the nerves of the brain and the spinal cord. This sheath is made of fatty substances and proteins. It is important because it helps in quick and undisrupted transmission of electric impulses from one neuron to the other neuron in an efficient manner.