Here's why:
* Cell Theory: The cell theory states that all living things are made up of one or more cells. This is the fundamental basis of life.
* Unicellular Organisms: Many organisms, like bacteria and some protists, exist as single cells.
* Multicellular Organisms: Larger organisms, like plants and animals, are composed of many cells that work together.
Even the simplest life forms require a cell as the basic unit of structure and function.
