Animal vs plant cells
Plant cells have cell wall + chloroplasts + permanent vacuole. Animal cells don't.
Both animal and plant cells have:
- Cell membrane (selectively permeable barrier).
- Cytoplasm (jelly-like material where reactions happen).
- Nucleus (contains DNA, controls cell).
- Mitochondria (respiration sites).
- Ribosomes (protein synthesis).
Plant cells ALSO have (animal cells don't):
- Cellulose cell wall β rigid, outside the membrane. Gives shape and support.
- Chloroplasts β green organelles containing chlorophyll. Site of photosynthesis.
- Large permanent vacuole β fluid-filled sac of cell sap. Provides turgor (firmness).
Drawing tips for Cambridge.
- Animal cell: roughly round/blob shape, no cell wall.
- Plant cell: rectangular shape (because of cell wall), label cell wall AND membrane separately.
Worked qualitative. Why are plant cells more rigid than animal cells?
- Cellulose cell wall: holds shape mechanically.
- Vacuole full of water: pushes outward against the wall (turgor pressure).
- Together: rigid box-like shape.
Cambridge tip. When labelling diagrams, label BOTH the cell wall AND the cell membrane in plant cells β they're different structures. Many students label only one.
- Animal: membrane, cytoplasm, nucleus, mitochondria, ribosomes.
- Plant: ALL OF ABOVE + cell wall + chloroplasts + vacuole.
- Cell wall = cellulose, RIGID, plant only.
- Both have cell membrane.