HISTOLOGY
URINARY SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Which of the following acts as the trigger for the initiation of micturition (voiding/urinating)?
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the stretching of the bladder wall
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motor neurons
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the pressure of the fluid in the bladder
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the sympathetic efferents
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Explanation:
Detailed explanation-1: -Smooth muscle stretch initiates the micturition reflex by activating stretch receptors in the bladder wall. This autonomic reflex causes the detrusor muscle to contract and the internal urethral sphincter muscle to relax, allowing urine to flow into the urethra.
Detailed explanation-2: -The parasympathetic nervous system stimulates the muscarinic stretch receptors in the bladder through the pelvic nerve fibers. When urine fills the bladder, the M3 receptors located within the bladder become stretched and stimulated, which leads to the contraction of the detrusor muscle for urination.
There is 1 question to complete.