Epithelial Transport of Glucose in Biosci107

Epithelial tissue

Cells arranged in continuous sheets, single or multiple layers.

Basement membrane

Layer cells sit on, separating from underlying tissues.

Tight junctions

Structures that restrict movement between epithelial cells.

Transcellular transport

Transport through epithelial cells, involving membranes.

Paracellular transport

Transport between epithelial cells, governed by diffusion.

Apical membrane

Membrane facing the lumen of an organ.

Basolateral membrane

Membrane facing the blood and basement membrane.

Glucose absorption

Process of glucose moving from lumen to blood.

Glucosuria

Presence of glucose in urine, often due to diabetes.

Sodium-glucose symporter (SGLT)

Transporter using Na+ gradient to absorb glucose.

Facilitative glucose transporter (GLUT)

Mediates glucose exit via passive diffusion.

Oral rehydration therapy

Uses glucose to enhance Na+ and water absorption.

Glucose-galactose malabsorption syndrome

Mutation in symporter causing sugar retention in intestine.

Renal threshold

Maximum glucose reabsorption capacity of kidney transporters.

Transport maximum

Point where glucose reabsorption saturates in kidneys.

Leaky epithelium

Type where paracellular transport is predominant.

Tight epithelium

Type where transcellular transport is predominant.

Electrical resistance

Measured resistance to ion flow through tight junctions.

Osmolarity

Concentration of solutes in a solution affecting water flow.

Counter ion

Ion that accompanies another ion to maintain charge balance.

Diabetes mellitus

Condition causing high blood sugar and glucosuria.

Ion gradients

Differences in ion concentration across membranes.

Water efflux

Movement of water out of cells due to osmolarity.

Transporters and channels

Proteins mediating secretion or absorption in epithelial cells.