Here's why:
* Self-sustaining: Cells are the smallest entities capable of carrying out all the processes necessary for life, such as metabolism, growth, reproduction, and response to stimuli.
* Fundamental building blocks: All living organisms are made up of one or more cells.
* Organelles: Cells contain specialized structures called organelles, each with specific functions that contribute to the overall life of the cell.
While there are smaller structures within cells, like molecules and atoms, these do not possess all the characteristics of life independently.
