Transport_in_and_out_of_cells_IGCSE_Biology.pptx

Transport in and out off cells

1. Transport in and out of cells IGCSE Biology 0610 – Two 40-minute lessons

2. Why transport matters Cells exchange materials for survival. Examples: Oxygen, CO₂, water, glucose, ions.

3. The cell membrane Semi-permeable bilayer with proteins. Controls entry and exit of substances.

4. Types of transport Diffusion (passive) Osmosis (passive) Active transport (energy required)

5. Diffusion Particles move from high to low concentration. Examples: Oxygen into blood, CO₂ out of cells.

6. Factors affecting diffusion Temperature ↑ → faster movement Surface area ↑ → faster rate Concentration gradient ↑ → faster diffusion Distance ↓ → faster diffusion

7. Osmosis Diffusion of water through a semi-permeable membrane. From high water potential → low water potential.

8. Osmosis in cells Animal cells: lysis or crenation Plant cells: turgid or plasmolysed.

9. Practical link Osmosis experiment with potato strips or Visking tubing.

10. Quick recap quiz Multiple choice questions on diffusion & osmosis.

11. Active transport Particles move against gradient. Requires ATP and carrier proteins.

12. Examples in organisms Root hair cells absorb minerals. Small intestine absorbs glucose.

13. Comparison summary Diffusion: no energy, high→low Osmosis: water only, high→low Active transport: uses energy, low→high

14. Importance of transport Maintains homeostasis. Enables nutrient uptake & waste removal.

15. Review task Complete worksheet or concept map on all processes.

16. Exit quiz / homework Define each transport process. Give examples and explain effects of surface area.

17. Well done! “Cells are never still — movement is life.”