<prompt> In proximal tubule, HCO3 is absorbed with the step ofNa Cl cotranspoerNa - K2Cl contraspoerNa - H exchangerNa -K exchanger  <response>: HCO3 is absorbed with the step of Na - H exchanger Ref: Ganongs review of medical physiology; 24th edition; page no; 680 Ref of imag : 