Question
Question: The most appropriate definition for neuroglial cells is that they are ______________. 1\. Nonsenso...
The most appropriate definition for neuroglial cells is that they are ______________.
1. Nonsensory supporting cells
2. Secretory cells
3. Sensory cells
4. Sensory and supporting cells
5. Nonsensory supporting and secretory cells
Solution
Neuroglial cells are specialized cells found in the brain and spinal cord supporting the neurons of both CNS and PNS and their fibers. Most of the cells in the glial system are the products of the neural crest.
Complete answer:
About 50% of all brain cells are neuroglial cells. They are non-sensory and are they two types: Macroglia and microglia.
Macroglial cells are those that regulate the retinal metabolism and modulate neuron function and blood vessels. They include the following:
Astrocytes are star-shaped cells that are typically found in the brain. They are responsible for the formation of the blood-brain barrier (BBB).
Ependymal cells are cubical cells forming the blood- CSF barrier. Their functions are not clear and they are under intense study. They secrete the cerebrospinal fluid (CSF).
Oligodendrocytes are myelinating cells of the central nervous system (CNS). Their homolog in the peripheral nervous system (PNS) is the Schwann cell.
Microglial cells are the smallest glial cells. They migrate around the nervous system they support the neurons by phagocytosing pathogens and other foreign bodies in the system.
Therefore correct answer is Option 1: Nonsensory supporting cells
Note: The neural crest is the remnant formed during the embryological process of neurulation (neural tube formation).
Glial cells rapidly regenerate, unlike neurons. In the case of neural damage, the glial cells multiply to occupy the damaged part. If their multiplication is uncontrolled; they may result in the formation of gliomas. They are benign but can turn malignant over time.
During the regeneration of a neuron (valerian degeneration regeneration phenomenon), the Schwan cells expand to conduct remaining impulses before the temporary loss of conductive function of neurons.