Common Misconceptions About Cell Transport
Part of Cell Transport — GCSE Biology
This common misconceptions covers Common Misconceptions About Cell Transport within Cell Transport for GCSE Biology. Diffusion, osmosis, active transport, factors affecting transport, surface area to volume ratio, and practical investigations It is section 14 of 18 in this topic. Use this common misconceptions to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 14 of 18
Practice
18 questions
Recall
20 flashcards
❌ Common Misconceptions About Cell Transport
❌ "Osmosis is just diffusion of water"
Incomplete — and incomplete gets no marks. Osmosis is specifically the movement of water molecules through a partially permeable membrane. Without mentioning the membrane, you will not get the mark. Osmosis is also NOT the movement of salt or solute — it is ONLY water.
❌ "Active transport and diffusion go in the same direction"
They are opposite. Diffusion moves substances from high to low concentration (down the gradient). Active transport moves substances from low to high concentration (against the gradient), using energy from ATP. The body uses active transport when diffusion would move things the wrong way — e.g. absorbing minerals through root hair cells where soil mineral concentration is lower than inside the cell.
❌ "Diffusion requires energy"
Diffusion and osmosis are both passive — they require NO energy. Only active transport requires energy (from ATP, produced by mitochondria). This is one of the most common exam errors.
❌ "Water always moves into cells"
Water moves from high water concentration to low water concentration. It can move INTO cells (making them turgid) or OUT of cells (making them flaccid/plasmolysed), depending on the concentration of the surrounding solution.
❌ "Larger organisms have better diffusion"
The opposite is true. Larger organisms have a smaller surface area to volume ratio, which makes simple diffusion less efficient. This is why they need specialised exchange surfaces (e.g. alveoli, villi, root hairs) to increase their surface area.