How they move
The structure used for movement differs with the organism — but all of them express the same characteristic.
| Structure | Used by | Example |
|---|---|---|
| Cilia | Unicellular organisms | Paramecium |
| Flagella | Unicellular organisms | Euglena, Chlamydomonas |
| Pseudopodia | Unicellular organisms | Amoeba |
| Muscles | Multicellular organisms | Humans, fish, birds |
There is movement inside a cell too
In the same way, the organelles inside cells also have the ability to move. So movement happens not only at an organism's largest scale but at its smallest. This movement is a living characteristic too; it is essential to their survival.
Locomotion is a subset of movement
Movement is a change in the position of the body or of a part of it. Locomotion is the whole organism going from one place to another. All locomotion is movement; not all movement is locomotion.