What is it?
Surface area is the outer layer of an cell/object.
Volume is the area inside of a cell/object.
When a object/cell is large the surface area to volume ratio is small. However, when the cell/object is small the surface area to volume ratio is larger meaning the rate of diffusion is more efficient.
Ficks Law and Rate of Diffusion
Diffusion is the net movement of particles in and out of a cell from a high to a low concentration.
Ficks Law is..
Rate of diffusion = (area of diffusion x difference in concentration ) / (thickness of surface over which diffusion occurs)
Rate of Diffusion is affected by;
- Surface Area, the greater the surface area the the greater the rate of diffusion.
- Thickness, of the surface. The thinner the surface the shorter pathway across the surface area meaning greater rate of diffusion.
- Concentration Gradient, the greater the difference in concentration the greater rate of diffusion.