Situated in the bladder wall are extend receptor cells. In the event the bladder fills to around 250 ml, the mucosal folds open and encourage these extend receptors. They ship signals into the pontine micturition Centre with the brain. The primary urinary system organs and also other urinary system constructions https://iwsite.blob.core.windows.net/mediacontainer/iwsite/media/THE-URINARY-SYSTEM.pdf