Simple Diffusion

What is diffusion?

Diffusion is the net movement of molecules from an area of high concentration to an area of low concentration.

Why is diffusion considered a passive process?

Because it doesn’t require energy.

In which state of matter does diffusion occur?

Diffusion only occurs in fluids.

What types of molecules can diffuse across membranes?

Small non-polar molecules can diffuse across membranes.

What does the rate of diffusion depend on?

The concentration gradient.

What happens when there is the same concentration on both sides of a membrane?

The rate of movement is equal, resulting in no net movement.

What occurs with a difference in concentration during diffusion?

More molecules move from a higher concentration to a lower concentration, resulting in net movement.

What is an example of gas exchange by diffusion?

Gas exchange in lung alveoli cells is an example of simple diffusion.

What types of gases can diffuse passively across the cell membrane?

Both carbon dioxide and oxygen, as they are small and non-polar.

Does gas exchange in the lungs require energy?

No, it happens without any energy input required.