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Report Thread starter 2 years ago
Few question that are baffling me...
Why is the constriction of bronchi and bronchioles controlled by the parasympathetic nervous system?
Why is the dilation of arterioles leading to the skin parasympathetic?
Why is the constriction of arterioles leading to the small intestine sympathetic?

Help please.
Much appreciated, thanks.
h lovibond
Badges: 2
Report 2 years ago
Hi there, first of all we need to understand the difference between the sympathetic and parasympathetic nervous system. The sympathetic nervous system is responsible for 'fight or flight', thus preserving life. The parasympathetic nervous system brings everything back to normal.

During 'fight or flight', more oxygen is needed at the muscles. Therefore bronchi and bronchioles relax to recieve a better air supply, arterioles constrict leading to the skin to conserve blood in the muscles and also to reduce bleeding should you be injured. Also blood is constricted at the small intestine as digestion is of little concern if you are being chased by a bear for example. This is all controlled by the sympathetic nervous system.

When everything calms down, the parasympathetic nervous system restores blood flow to the skin, restores blood flow to the small intestine and reconstricts the bronchi and bronchioles back to normal function.

Hope this helps.

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