<prompt> Which of the following transpo processes is passive?Co-transpo of Na ion and a molecule into cellExchange of K ion outside the cell for Na ion inside the cellFlow of H2O through cell membrane by osmosisUptake of molecules into cell by endocytosis  <response>: Osmosis is the movement of water molecules across a semi-permeable membrane from a region of Lower solute concentration to an area of higher solute concentration. It is passive in nature. REF: TEXTBOOK OF MEDICAL PHYSIOLOGY GEETHA N 2 EDITION, PAGE NO - 3 