Urine Storage Ureters: muscular tubes that are about 25cm long and connect the kidney to the bladder Layers 2 smooth muscle, 1 connective Urine enters the ureters causing it to stretch which stimulates the surrounding smooth muscle to start a peristaltic wave to push urine to bladder

Bladder Is muscular sac that holds urine The bladder has rugae or wrinkles that stretch due to urine pressure Stretch receptors reach threshold and send a message to the brain to cause urge to void

Urethra A thin walled tube that starts with the internal urethral sphincter and is caped with the external urethral sphincter Only the external urethral sphincter can be voluntarily controlled

Voiding The process of voiding urine is called micturition This process is controlled by the sympathetic nervous system The bladder is told to constrict by the CNS as the interior and exterior urethral sphincters are told to relax