Major calyx

The major calyx surrounds the apex of the 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 renal pelvis into the ureter.

Peristalsis of the smooth muscle originating in pace-maker cells originating in the walls of the calyces propels urine through the pelvis and ureters to the bladder.