14.3 Basic Renal Processes

Apical Membrane

The surface of an epithelial cell that faces a lumen, such as that of the intestines; also known as luminal membrane

Basolateral Membrane

Sides of epithelial cell other than luminal surface; also called serosal or blood side of cell

Filtered Load

Amount of any substance filtered from renal glomerular capillaries into Bowman’s capsule

Glomerular Filtrate

Ultrafiltrate of plasma produced in the glomerulus that is usually free of cells and large proteins

Glomerular Filtration

Process by which components of plasma in the glomerular capillary are passed to the Bowman’s space of the glomerulus; process is governed by net glomerular filtration pressure

Glomerular Filtrate Rate (GFR)

Volume of fluid filtered from renal glomerular capillares into Bowman’s capsule per unit time

Net Glomerular Filtration Pressure

Sum of the relevant forces resulting in glomerular filtration; the hydrostatic pressure within the glomerular capillary (G[PC]) minus the hydrostatic pressure in Bowman’s space (P[BS]) and minus the osmotic force in the glomerular capillary (π[GC])

Transport Maximum (Tm)

Upper limit to amount of material that carrier-mediated transport can move across the renal tubule

Tubular Reabsorption

Transfer of materials from kidney tubule lumen to peritubular capillaries

Tubular Secretion

Transfer of materials from peritubular capillaries to kidney tubule lumen