Adaptations for Rapid Transport
- The rate at which diffusion (including both simple diffusion and facilitated diffusion) occurs across external and internal cell membranes varies
- Some cells are adapted for rapid transport (diffusion) of molecules across their internal or external membranes
- The rate of diffusion depends on several factors. These include:
- Temperature
- The surface area of the exchange surface
- The concentration gradient across the exchange surface
- The thickness of the exchange surface
Simple diffusion
The rate of simple diffusion depends on three main factors:
Facilitated Diffusion
The rate of facilitated diffusion depends on two main factors