<prompt> Proteins are transported into the cell by?PinocytosisOsmosisActive diffusionPassive diffusion  <response>: Ans. a Pinocytosis. Ref. Ganong, Physiology, 21stpg.29Pinocytosis Cell drinking It is the process by which proteins are taken into the cell. The substance ingested are insoluble not seen by microscope. Endocytosis: It is a process by which a molecule is taken into the cell. Endocytosis can be of 2 types: Phagocytosis pinocytosis. Endocytosis can be constitutive or clathrin-mediated, which is responsible for internalisation of many receptors ligands binding to them. e.g. NGF, LDL, Synaptic function. 