Factors Affecting Cell Membrane Transport

Surface Area to Volume Ratio

A measure that describes how much surface area a cell has relative to its volume. It affects the cell's ability to receive inputs and remove wastes.

What happens to the surface area to volume ratio as cells increase in size?

The surface area to volume ratio decreases.

What can increase a cell's surface area to volume ratio?

Specialised shapes of some cells.

Concentration Gradient

The difference in concentration that drives diffusion.

How does the concentration gradient affect the rate of diffusion?

The greater the difference in concentrations, the faster the rate of diffusion.

What is the trend regarding the size of molecules and their diffusion rate?

Larger molecules diffuse slower and may be too large to move through the cell membrane.

How do non-polar molecules differ from polar molecules in terms of diffusion through the cell membrane?

Non-polar molecules diffuse readily, while polar molecules require the use of proteins.