Cells and organelles
Animal and plant cells
All living things are made of cells. Animal and plant cells are both eukaryotic — they have a nucleus and other membrane-bound organelles.
Most animal and plant cells have these structures in common:
- Nucleus
- Cytoplasm
- Cell membrane
- Mitochondria
- Ribosomes
Plant cells also have a cell wall, a permanent vacuole, and often chloroplasts.
Key terms
What each organelle does
Each organelle has a specific job:
- The contains genetic material and controls the cell's activities.
- are the site of aerobic respiration, releasing energy the cell needs.
- are where proteins are made.
- Plant absorb light energy to make food by photosynthesis.
See AQA specification for the full list of required structures.
Key terms
The other structures
The rest of a cell's structures each have a job too:
- The controls which substances pass into and out of the cell.
- The is a jelly-like liquid where most of the cell's chemical reactions happen. The organelles sit in it.
- The , found in plant cells and algae, is made of . It strengthens the cell and stops it bursting when it takes in water.
- The is filled with cell sap, a solution of sugars and salts. It keeps the cell firm, which helps to support the plant.
Key terms
Comparing animal and plant cells
| Structure | Animal cell | Plant cell |
|---|---|---|
| Nucleus, cytoplasm, cell membrane | Yes | Yes |
| Mitochondria, ribosomes | Yes | Yes |
| Cell wall | No | Yes |
| Permanent vacuole | No | Yes |
| Chloroplasts | No | Often |
Not every plant cell has chloroplasts. grow underground, where there is no light to photosynthesise with, so they have none.
Common mistake
The cell wall and the cell membrane are different structures. Plant cells have both: the membrane controls what goes in and out, and the wall outside it gives strength.