Key learning points

1. All organisms (including animals, plants, fungi and micro-organisms) are made up of one or more living cells.
2. All cells have some structures in common (cell membrane and cytoplasm) and have a three-dimensional shape.
3. Chemical reactions essential to life occur in cytoplasm; the cell membrane regulates the cell’s internal environment.
4. Many animals and plants are multicellular; they are made up of many cells organised to form tissues and organs.
5. Micro-organisms such as bacteria are unicellular – they are made of just one cell.

Keywords

• Organism - A living thing made of one or more cells.

• Cell - The basic unit of all forms of life.

• Multicellular - An organism made of many cells.

• Micro-organism - An organism that can only be viewed through a microscope.

• Unicellular - An organism that consists of a single cell.

Common misconception