Calyces

Calyces surround the appex of the malpighian pyramids. Urine formed in the kidney passes through a papilla at the apex into a minor calyx then into major calyx before passing through the pelvis into the ureter. Peristalsis of the smooth muscle originating in pace-maker cells originating in the walls of the calyses propels urine through the pelvis and ureters to the bladder.