Cell BiologyComparison
Diffusion vs Osmosis vs Active Transport: Side-by-Side
Part of Cell Transport — GCSE Biology
This comparison covers Diffusion vs Osmosis vs Active Transport: Side-by-Side within Cell Transport for GCSE Biology. Diffusion, osmosis, active transport, factors affecting transport, surface area to volume ratio, and practical investigations It is section 10 of 18 in this topic. Use this comparison to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 10 of 18
Practice
18 questions
Recall
20 flashcards
⚖️ Diffusion vs Osmosis vs Active Transport: Side-by-Side
Figure: Comparing the three types of cell transport
| Feature | Diffusion | Osmosis | Active Transport |
|---|---|---|---|
| What moves? | Any particles (gases, ions, small molecules) | Water molecules only | Specific molecules / ions (e.g. glucose, mineral ions) |
| Direction | High → Low concentration (down gradient) | Dilute → Concentrated (down water concentration gradient) | Low → High concentration (AGAINST gradient) |
| Energy required? | No — passive | No — passive | Yes — ATP from mitochondria |
| Membrane needed? | Not necessarily (can occur in air/water) | Yes — must be partially permeable | Yes — uses protein carrier molecules in membrane |
| Concentration gradient? | Required (high to low) | Required (low water concentration pulls water in) | Works against gradient |
| Body examples | O2 into blood at alveoli; CO2 out of cells | Water into root hair cells from soil; water reabsorption in kidneys | Glucose absorption in small intestine; mineral ions into root hair cells from soil |
| Plant examples | CO2 into leaf cells for photosynthesis | Water entering root cells from soil | Mineral ions (nitrate, phosphate) into root hair cells |