GENERAL HISTOLOGY

Detailed explanation-1: -Active transport driven by the Na+ gradient is responsible for the uptake of glucose from the intestinal lumen. The transporter coordinately binds and transports one glucose and two Na+ into the cell.

Detailed explanation-2: -In the intestine and renal proximal tubule, glucose is transported against a concentration gradient by a secondary active transport mechanism in which glucose is cotransported with sodium ions.

Detailed explanation-3: -In brief, transport across an epithelial cell can be divided into those that do not require a protein, and those that are protein-mediated. The former is termed simple diffusion and is passive, being dependent on the concentration gradient and surface area.

Detailed explanation-4: -Glucose transport across cell membranes can occur by carrier-mediated active transport or by a concentration gradient-dependent facilitated transport that requires a specific carrier.

Detailed explanation-5: -Glucose from digested food enters intestinal epithelial cells by active transport.