The success of oral rehydration therapy of diarrhea depends upon which of the following processes in the intestinal mucosa?: (A) Sodium pump mediated Na+ absorption, (B) Glucose coupled Na+ absorption, (C) Bicarbonate coupled Na+ absorption, (D) Passive Na+ diffusion secondary to nutrient absorption
Answer is B. Glucose coupled Na+ absorption from GIT remain patent even in presence of severe diarrhea whereas other mechanisms may fail. Thus, glucose is added in the ORS.