The kidneys are of outstanding importance. They perform a number of homeostatic functions including filtration of plasma and elimination of metabolic waste products, regulation of the composition and volume of the extracellular fluid, and regulation of blood pressure. The kidneys are also endocrine organs. Test your basic knowledge of renal physiology by taking this simple quiz.
(1) In the epithelial cells of the kidney proximal tubules, the basal infoldings increase the surface area of the basal membrane by approximately a factor of:
(2) When considering the permeability of epithelia, the transepithelial resistance (Rt) of leaky epithelia falls in this range:
(3) When considering the permeability of epithelia, the transepithelial resistance (Rt) of tight epithelia falls in this range:
(4) Which of the following epithelia is expected to exhibit a higher numerical value (positive or negative) for its transepithelial potential (Vt)?
(5) In the epithelial cells of the kidney proximal tubules, the Na+/K+ ATPase is localized to the __________ membrane