Final answer:
The urine-forming portion of the kidney is made up of the renal cortex, medulla, and renal pelvis.
Step-by-step explanation:
The urine-forming portion of the kidney is made up of three regions: the renal cortex, the medulla, and the renal pelvis.
The renal cortex contains the nephrons, which are the functional units of the kidney. The medulla is located in the middle and contains the renal pyramids and renal papillae. The renal pelvis collects urine and leads to the ureter.
Overall, the kidney filters blood and produces urine through the actions of nephrons.