Cell Transport Flashcards
What is simple diffusion?
The net movement of molecules from an
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
What factors affect the rate of diffusion? (3)
● Temperature
● Concentration gradient
● Surface area (to volume ratio) of cell membrane
Define osmosis
The net movement of water molecules from
an area of high water concentration to an
area of low water concentration through a
partially permeable membrane
What is 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
How is a percentage change in mass calculated?
% change = (final mass - initial mass)/initial mass x 100
Define concentration gradient
The difference in concentration between two areas
What happen when the concentration of both solutions are equal in Osmosis?
There will be no net movement of water molecules.