The surrounding cell walls and membranes can control the materials that pass in, out and through living cells. Four processes that can be related to this movement of materials are diffusion, osmosis, pinocytosis and phagocytosis.

To perform their functions, cells must maintain an internal steady state in the midst of an ever-changing environment. This consistency, or ‘homeostasis’, is maintained in part by the regulation of the movement of materials in and out of the cell. To achieve this control, a cell is bounded by a delicate membrane, which can distinguish between substances, slowing down or stopping the movement of some while allowing others to pass through freely. Because not all substances penetrate the cell membrane equally well, the membrane is known as being ‘differentially’, or ‘selectively permeable’.

The main purpose of the cell membrane is to regulate the movement of materials in and out of the cell. By doing so, the cell’s internal environment can di

Some topics in this essay:
, Osmosis Osmosis, Diffusion Diffusion, Pinocytosis Pinocytosis, C3a C5a, Phagocytosis Phagocytosis, cell membrane, movement materials, cell wall, cell walls, active transport, active transport type, water molecule concentration, diffusion osmosis pinocytosis, transport type, ‘active transport’, encapsulated bacteria, materials pass, movement materials cell, solute concentration, osmosis pinocytosis phagocytosis,