Calyx (anatomy) kidney, a conglomeration of two or three minor calyces to form a major calyx, or the Calyx of Held, a particularly large synapse in the mammalian auditory central nervous system, named by H. Held in his 1893 article "Die centrale Gehörleitung", due to its flower-petal-like shape. In male insects, a funnel-shaped expansion of the basal part of the "vas deferens" (part of the seminal duct). Also in entomology, a flattened cap of neuropile in an insect brain (a component of the corpus pedunculatum) and by certain female insects, an expansion of the oviduct into which the ovarioles open. Calyx (anatomy)
Renal calyx Renal calyx The renal calyces are chambers of the kidney through which urine passes. The minor calyces surround the apex of the renal pyramids. Urine formed in the kidney passes through a renal papilla at the apex into the minor calyx; two or three minor calyces converge to form a major calyx, through which urine passes before continuing 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 renal pelvis and ureters to the bladder. The initiation is caused by the increase in