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Edexcel IGCSE Biology · Spec 2.16

Factors Affecting Diffusion and Movement Rate

Covers recall the four factors affecting movement rate, Explain each factor using particles and Apply the factors to biological exchange surfaces.

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Factors Affecting Diffusion and Movement Rate

Spec 2.16

What you need to know

  • Recall the four factors affecting movement rate
  • Explain each factor using particles
  • Apply the factors to biological exchange surfaces

Active recall

Quick check

Answer each question before opening the answer.

Name the four factors affecting movement rate

Surface area-to-volume ratio, distance, temperature and concentration gradient

Why do one-cell-thick walls increase diffusion rate?

They create a short diffusion distance

How does ventilation maintain rapid oxygen diffusion?

It replaces oxygen-depleted air and maintains a steep oxygen concentration gradient

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