Endocrine System: Overview

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Nervous Tissue
1. a. Contrast the physical differences between neuroglia (glial) cells and neurons.
The physical differences between neuroglia and neurons
are the following: a neuron contains specifically distinct parts
like the dendrite, cell body, and axon. The dendrites are the
branch-like processes that are the neuron’s receptors. The cell body
ontains a centrally located nucleus with clumps of endoplasmic
reticulum (Nissl bodies) within the cytoplasm. The axons are the
lengthy processes that can be coated or non-coated, which act
as the transmitting arm of the neuron. Neuroglial cells are many
in number and shape. These helper/support cells of the nervous
system and differ in the fact that they are non- conductive.
b. Describe the histological diversity seen in the nervous system.
The histological assortment is evident in the variety of cells that aid in the nervous system.
It can be seen in the following discussion of cell types.
2. Identify and describe the functions of the six types of neuroglia.
Astrocytes – sustains the neurons by
keeping the fluid milieu surrounding
the neurons as action potential
friendly.
Oligodendrocytes – provide neurons
with myelinated sheaths and establish
an assistance network for neurons.
Microglia – are guardian cells that
protect the nervous system from
microbial invaders.
Ependymal cells – are specialized
epithelial tissue that produce cerebrospinal fluid and help move it via its cilia throughout the CNS.
Schwann cells – creates myelination around axons of the peripheral nervous system.
Satellite cells – provide neuronal assistance at the peripheral nervous system.
Of the six types of neuroglia, astrocytes, oligodendrocytes, microglia, and ependymal cells are found only
in the CNS. Schwann cells and satellite cells are present in the PNS.
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3. a. Identify each of the following structures in both the diagrammatic and photomicrograph views of
the neuron.
b. Describe the general function of:
neurons – these are the conductive nerve cells of the body which generate and transmit action
potentials that convey information..
dendrites – these are nerve cell fibers that conduct impulses towards the neuron cell body.
axons – these are nerve cell fibers that conduct impulses away from the neuron cell body.
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