kidney
Which of the following statements about the kidney is false? a. The renal pelvis drains into the ureter. The renal pyramids are in the medulla. The cortex covers the capsule. Nephrons are in the renal cortex. Because the kidney filters blood, its network of blood vessels is an important component of its structure and function. The arteries, veins, and nerves that supply the kidney enter and exit at the renal hilum. Renal blood supply starts with the branching of the aorta into the renal arteries which are each named based on the region of the kidney they pass through and ends with the exiting of the renal veins to join the inferior vena cava. The renal arteries split into several segmental arteries upon entering the kidneys. Each segmental artery splits further into several interlobar arteries and enters the renal columns, which supply the renal lobes. The interlobar arteries split at the junction of the renal cortex and medulla to form the arcuate arteries. The arcuate bow shaped arteries form arcs along the base of the medullary pyramids. Cortical radiate arteries, as the name suggests, radiate out from the arcuate arteries. The cortical radiate arteries branch into numerous afferent arterioles, and then enter the capillaries supplying the nephrons. Veins trace the path of the arteries and have similar names, except there are no segmental veins. As mentioned previously, the functional unit of the kidney is the nephron, illustrated in Figure 41.6. Each kidney is made up of over one million nephrons that dot the renal cortex, giving it a granular appearance when sectioned sagittally. There are two types of nephrons cortical nephrons 85 percent , which are deep in the renal cortex, and juxtamedullary nephrons 15 percent , which lie in the renal cortex close to the renal medulla. A nephron consists of three partsa renal corpuscle, a renal tubule, and the associated capillary network, which originates from the cortical radiate arteries.