Principles of SA:V Surface area?and?volume?are both very important factors in the?exchange of materials?in organisms The surface area refers to the?total area of the organism that is exposed to the...
Investigating Diffusion Investigating diffusion using Visking tubing Visking tubing?(sometimes referred to as dialysis tubing) is a non-living?partially permeable?membrane made from cellulose Pores...
Investigating Diffusion & Osmosis: Plant Tissue Investigating diffusion The?permeability?of cell membranes can be affected by environmental factors such as?chemicals or temperature This can be ...
Endocytosis & Exocytosis The processes of diffusion, osmosis and active transport are responsible for the transport of?individual molecules or ions?across cell membranes However, the?bulk trans...
The Process of Active Transport Active transport is the?movement of molecules and ions through a cell membrane from a region of lower concentration to a region of higher concentration using energy ...
The Process of Osmosis All cells are surrounded by a cell membrane which is?partially permeable Water can move in and out of cells by?osmosis Osmosis is the?diffusion of water molecules?from a dilu...
Diffusion & Facilitated Diffusion Diffusion is a type of?transportation?that occurs?across the cell membrane It can be defined as: The net movement, as a result of the random motion of its mole...
Cell Signalling Cell signalling is the process by which messages are sent to cells Cell signalling is very important as it?allows multicellular organisms to control / coordinate their bodies and re...
Cell Surface Membranes Phospholipids Form the basic structure of the membrane (phospholipid bilayer) The tails form a hydrophobic core comprising the innermost part of both the outer and inner laye...
Phospholipids, Cholesterol, Glycolipids, Proteins & Glycoproteins The cell membranes of all organisms generally have a similar structure Cell membranes contain several different types of molecu...
The Fluid Mosaic Model of Membranes Membranes are vital structures found in all cells The cell surface membrane creates an enclosed space separating the internal cell environment from the external ...
Enzyme Activity: Immobilised v Free Enzymes can be added to?solutions?and are thereby considered?‘free’?or they can be?immobilised Immobilised enzymes are enzymes that have been bound to an?inert,?...
