Molecules will diffuse from areas of higher concentration to lower concentration across cell membranes. Smaller particles and molecules diffuse faster than larger ones. Diffusion occurs more quickly through thin membranes and over shorter distances, or with increased surface area or temperature, as higher temperatures provide particles with greater kinetic energy for faster movement.

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Foods Ltd

2. CONCENTRATION GRADIENT
If a substance is more concentrated outside a cell
than inside, the molecules will tend to diffuse
into the cell
If a substance is more concentrated inside the
cell than outside, the molecules will tend to
diffuse out of the cell
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3. The concentration of
oxygen molecules is
greater outside the cell
than inside
So the oxygen molecules
diffuse into the cell
CONCENTRATION GRADIENT
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4. SIZE OF CELLS
Smaller particles tend to diffuse faster than larger
molecules
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5. DIFFUSION PATHWAY
Diffusion takes place more quickly through thin
membranes because there is only a short diffusion
pathway.The shorter the distance between the two
regions , the faster the rate
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6. Diffusion is quicker if membrane has a large
surface area
12
SURFACE AREA

7. Increase in temperature increases rate of diffusion because
particles have greater kinetic energy.
TEMPERATURE 13