Thus, at the end of the tubular system, the result is a very concentrated fluid containing
the nitrogenous wastes. This concentrated fluid is called urine.
Figure 8-2. A "typical" nephron.
8-4. COLLECTION OF URINE
The urine from each nephron flows into a collecting tubule (straight renal tubule).
The collecting tubules merge until they form one of the papillary ducts that open at the
papilla of the renal pyramid. At the papilla, the urine empties into the calices. The urine
then flows into the renal pelvis in the sinus of the kidney.
Section II. OTHER PARTS OF THE HUMAN URINARY SYSTEM
8-5. THE URETERS
The ureter is a tubular structure that is continuous with the renal pelvis. The
ureter of each kidney passes down the posterior abdominal wall on its respective side.