Q.Name the smooth muscle of urinary bladder.

Urinary Bladder and Micturition

The kidneys make urine continuously, drop by drop — but we do not urinate continuously. The body solves this with a storage organ, the urinary bladder, and a controlled release process called micturition. The design cleverly combines involuntary and voluntary control.

The urinary bladder — a stretchy store

Urine formed by the kidneys drains through the ureters into the urinary bladder, a muscular, highly distensible (stretchable) sac. Its wall contains smooth muscle called the detrusor muscle. As urine collects, the bladder wall stretches to accommodate it without a big rise in pressure, letting urine be stored until it is convenient to release.

The exit and its two guards

Urine leaves the bladder through the urethra, guarded by two sphincters:

• An internal urethral sphincter of smooth muscle — involuntary.
• An external urethral sphincter of skeletal muscle — under voluntary control.

This double gate is what allows conscious control of when we urinate.

Micturition — the act of urination …