Kidney urine filtration

The kidney, the organ for filtration and production of urine. The left kidney (in blue) is shown in section with the nephrons (in orange-yellow). It is through the renal artery and vein as well as the internal vascularization of the kidney at the level of the cortex that the blood (red arrows) passes by the kidney. The kidney is an organ that filters blood and produces urine (blue arrows). The renal parenchyma contains the nephrons which filter the blood and produce urine. Thus, the urine produced in the nephrons is collected at the level of the chalices and pelvis (in dark blue). (Photo by: BSIP/Education Images/Universal Images Group via Getty Images)