GENERAL HISTOLOGY

Detailed explanation-1: -The internal urethral sphincter regulates involuntary control of urine flow from the bladder to the urethra, and the external urethral sphincter provides voluntary control of urine flow from the bladder to the urethra.

Detailed explanation-2: -The primary function of the detrusor muscle is to contract during urination to push the urine out of the bladder and into the urethra. The detrusor muscle will relax to allow the storage of urine in the urinary bladder.

Detailed explanation-3: -Both muscles function in a similar fashion. When one relaxes the voluntary muscle, the involuntary muscle relaxes as well. When these muscles are relaxed, they open up allowing for urine to flow out of the bladder through the urethra and out the body. When these muscles are contracted, they keep urine in the bladder.

Detailed explanation-4: -Unlike the internal sphincter muscle, the external sphincter is made of skeletal muscle, therefore it is under voluntary control of the somatic nervous system.

Detailed explanation-5: -A ring-shaped muscle that relaxes or tightens to open or close a passage or opening in the body.