Bosh miya yarim sharining po’stloq qismi, uning tuzilishi. Reja

Combined Solid and Water Transport

See Chapter 10: Renal Tubules and Collecting Ducts.

Active Transport

Active transport is the transport of substances through the cell membrane

by means of an energy-consuming transport system (transport

ATPase). Here, again, ATP serves as universal fuel. Such a transport

process can move a substance through the membrane against a concentration

gradient (Fig. 1.14). Thus cells have the ability to maintain in

their interior stable ion concentrations, for example, that are clearly

different from their concentrations in the extracellular fluid. These active

transport processes are served by specialized proteins in the cell

membrane that can move several ions simultaneously. In this process,