Sympathetic Nervous System Essay

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Sympathetic nervous system is the one that will be engaged. This is because; sympathetic nervous system normally functions to produce reflex adjustments and localized adjustments of the cardiovascular system. Under conditions of stress, activation of the entire sympathetic nervous system occurs producing the fight-or-flight response. What characterizes this response is an increase in heart rate, epinephrine release from the adrenal gland in large quantities, vasodilation of the skeletal muscle, cardiac output increase, vasoconstriction of cutaneous and gastrointestinal, dilation of pupillary piloerection and bronchial dilation. Preparing the individual for imminent danger is the overall effect (Bechir 2010).
What would be the effects of this system on your:
Name Effect
Eyes Dilation of pupillary, focusing for distance vision
Skin Increases secretion of sweat glands, contraction and erection of hair
Respiratory system Increases the diameter of airways, increases the rate of respiratory
Skeletal Muscle Increases force of
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Vasoconstriction results due to activation of a1 receptors by epinephrine or norepinephrine, in the arteries of the heart. Whereas, a1 receptors lack in the vessels in skeletal muscle since they need to remain open to receive the increased flow of blood from the heart during the response of fight-or-flight. The nerve cell bodies that lie on either side of the spinal cord are the ganglia of the sympathetic nervous system. Those that exit the spinal cord synapse within these ganglia are preganglionic sympathetic fibers. Acetylcholine, Ach is the ganglionic neurotransmitter. Ach release from preganglionic synapse binds to nicotinic Ach receptors on the postganglionic cell. Postganglionic neuron is depolarized by Ach binding generating an action potential that elicits a response by traveling to the target

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