Question

why is the cell theory only a theory

Answer 1

as opposed to?

Answer 2

The cell theory isn't a cell theory for atleast 2 reasons.

The first reason that the cell theory is a theory is that viruses are a big exception to it. Viruses are not made of cells, and they don't have a metabolism and the activity of an organism depends on chemical reactions, but some scientists still consider them to be alive, so that goes against what the cell theory says.

The second reason is simple...the first cell in the world obviously did not come from a preexisting cell.

The cell theory states:
1. All living things are made of one or more cells
2. Cells only come from preexisting cells
3. Cells are the smallest unit of life