Factors Affecting Diffusion
Biology: AQA GCSE Higher, topic 1.3.2
Factors Affecting Diffusion
The rate of diffusion can speed up or slow down based on the following factors:
Concentration gradient
- The concentration gradient is linked to the difference in concentration between two areas.
- The bigger the difference in concentration between two areas, the greater the concentration gradient and the faster the rate of diffusion.
Temperature
- The higher the temperature, the faster the rate of diffusion.
Membrane surface area
- The larger the surface area of the membrane that a substance is diffusing through (e.g. the membrane around a cell), the faster the rate of diffusion.
Test yourself on Factors Affecting Diffusion
What would happen to the rate of diffusion if the concentration gradient decreased?
What would happen to the rate of diffusion if the concentration gradient became steeper and the temperature increased?
What is diffusion?
A gas has a higher concentration outside a cell than inside the cell. In which direction will the gas diffuse?
A substance diffuses slowly across a membrane that has a small surface area and a low temperature. What would happen to the rate of diffusion if the surface area was increased and the temperature was raised?