The NET movement of molecules from a area of high concentration to an area of low concentration down a concentration gradient.
What molecules enter and leave cells via simple diffusion through the cell membrane?
Small molecules, e.g. oxygen, water, glucose, amino acids
Define osmosis.
The NET movement of water molecules from an area of highwaterconcentration to an area of low water concentration through a partially permeable membrane.
Define active transport.
The movement of molecules across a cell membrane from an area of low concentration to an area of high concentration, against the concentration gradient, using energy.
Percentage change calculation.
% change = (final mass - initial mass)/initial mass x 100