Definition of Renal pelvis

The renal pelvis or pelvis of the kidney is the basin-like or funnel-like dilated proximal part of the ureter in the kidney. In humans, the renal pelvis is the point of convergence of two or three major calyces. Each renal papilla is surrounded by a branch of the renal pelvis called a calyx. The major function of the renal pelvis is to act as a funnel for urine flowing to the ureter. The renal pelvis is the location of several kinds of kidney cancer. Its mucous membrane is covered with transitional epithelium, and an underlying lamina propria of loose to dense connective tissue.
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