ANATOMY

Detailed explanation-1: -The wall of the bladder is comprised of smooth muscle fibers oriented in multiple different directions. These smooth muscle fibers are collectively known as the detrusor muscle. This interwoven orientation provides the bladder with the ability to stretch in response to the presence of urine.

Detailed explanation-2: -The detrusor smooth muscle is the main muscle component of the urinary bladder wall. Its ability to contract over a large length interval and to relax determines the bladder function during filling and micturition.

Detailed explanation-3: -The detrusor muscle, also detrusor urinae muscle, muscularis propria of the urinary bladder and (less precise) muscularis propria, is smooth muscle found in the wall of the bladder.

Detailed explanation-4: -The bladder wall contains two smooth muscle layers: (1) an outer layer of longitudinal to obliquely arranged muscle fibers and (2) an inner layer of transversely or circularly arranged muscle fibers.

Detailed explanation-5: -The detrusor is the smooth or involuntary muscle of the bladder wall. The urethral muscles consist of the external and internal sphincter. The internal sphincter and detrusor muscle are both under autonomic control. The external sphincter, however, is a voluntary muscle under the control of voluntary nerves.