No, only living things are made up of cells. This is one of the fundamental principles of cell theory.

Here's why:

* Cell Theory: This theory states that all living organisms are composed of one or more cells. It also states that cells are the basic unit of structure and function in living organisms.

* Non-Living Things: Non-living things, such as rocks, water, or air, are not made up of cells. They are made up of different types of matter, but they do not have the characteristics of life, such as metabolism, reproduction, or growth.

Therefore, only living organisms are composed of cells.