What role does the renal pelvis play in the urinary system?

The renal pelvis serves a critical function in the urinary system as the structure that collects urine produced by the kidneys before it flows into the ureters. Located at the center of each kidney, the renal pelvis acts as a funnel that gathers urine from the collecting ducts, allowing it to accumulate in preparation for transport to the bladder. This anatomical arrangement is essential for the efficient flow of urine, as it ensures that all the urine generated by the kidney's nephrons is directed towards the ureters for elimination from the body.

The other options describe functions that are not associated with the renal pelvis. Nutrient absorption is primarily a function of the intestines rather than the urinary system. Storing urine is the role of the bladder, where urine is held until it is ready to be excreted from the body. Filtering blood describes the process executed by the nephron within the kidneys rather than the renal pelvis itself. Therefore, the role of the renal pelvis is specifically to collect urine from the kidneys.