<prompt> Which of the following does not have a Tm value?NaUreaCreatinineGlucose  <response>: Transpo maximum Tm or tubular maximum : is the maximum amount of a substance that can be transpoed across the tubule reabsorbed or secreted per unit time.E.g., glucose has a Tm value of 320 mgmin. Reabsorption or secretion of most substances is mediated by their respective carrier proteins in the wall of the tubules. Tm implies saturation of the carrier. Since Na reabsorption primarily involves the activity of NaK pump which does not exhibit saturation kinetics, Na reabsorption does not have a Tm value. 