34.
In the ANS, the number of neurons connecting the CNS with a visceral organ is
always two. The cell bodies of the second neurons form a collection outside the
CNS, called a ganglion. The first neuron extends from the CNS to the ganglion
and is therefore called the preganglionic neuron. Cell bodies of the second
neurons make up the ganglion. The second neuron's processes extend from the
ganglion to the visceral organ. Thus, the second neuron is called the post-
35.
The efferent pathways of the ANS fall into two major divisions. The one most
active during a "fight-or-flight" reaction is the thoraco- lumbar outflow (sympathetic
nervous system). The other is the cranio- sacral outflow (parasympathetic
36.
The intermediolateral gray columns from the T-1 to the L-2 levels of the spinal cord
are made up of the cell bodies of the preganglionic sympathetic neurons. The
sympathetic ganglia are made up of the post- ganglionic sympathetic neurons.
The sympathetic NS activates those visceral organs needed to mobilize energy for
action. It deactivates those which are not needed. (para 11-17)
37.
Four pairs of nuclei in the brainstem and the intermediolateral gray columns at the
S-2 through S-4 levels of the spinal cord are made up of the cell bodies of the
preganglionic parasympathetic neurons. The intramural ganglia within the walls of
the central visceral organs are made up of the cell bodies of the post-ganglionic
parasympathetic neurons. As compared to that of the sympathetic NS, the
parasympathetic NS has the opposite effect on visceral organs. (para 11-18)
38.
A pathway is the series of nervous structures utilized in the transmission of an item
39.
The neuraxis is the brainstem and the spinal cord, considered together as one
40.
A sensory pathway is a series of nervous structures used to transmit information
41.
A motor pathway is a series of nervous structures used to transmit information
42.
The human nervous system has several levels of control. The lowest level is the
simple reflex arc. The highest level is the conscious level. Between, there are
several progressively higher levels. All information input and all information output
are monitored and evaluated. (para 11-19c)43.The right half of the brain controls
the left side of the body. The left half of the brain controls the right side of the
MD0006
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