Explain micturition.

(N/A) Micturition is the process by which urine is expelled from the urinary bladder.
As urine accumulates in the bladder,its muscular walls stretch.
This stretching stimulates sensory nerves in the bladder wall,which sends signals to the central nervous system,initiating a micturition reflex.
This reflex triggers the urge to urinate.
To release urine,the urethral sphincter relaxes while the smooth muscles of the bladder wall contract.
This coordinated action forces urine out of the body through the urethra.
An adult human typically excretes about $1-1.5 \text{ litres}$ of urine per day.