Final answer:
The hilum is the part of the kidney that contains the renal artery, renal vein, and ureter. It is essential for the entry and exit of structures that serve the kidney's function.
Step-by-step explanation:
The part of the kidney that contains the renal artery, renal vein, and ureter is the hilum. Specifically, the renal hilum is the entry and exit site for structures servicing the kidneys. It is here that one would find the arrangement of the renal artery, vein, and renal pelvis in an anterior-to-posterior order. The hilum is also the site where the renal pelvis emerges and funnels urine into the ureter. Each of these components plays a vital role in kidney function, with the renal arteries supplying blood, the renal veins carrying cleansed blood back to the circulation, and the ureter transporting urine to the bladder.