Cell theory states that the cell is the basic unit of living organisms.
Before the discovery of the cell, people were unaware that living organisms were made of building blocks like cells.
Cell theory is one of the basic theories of biology.

Cell theory states that the cell is the basic unit of living organisms.
Before the discovery of the cell, people were unaware that living organisms were made of building blocks like cells.
Cell theory is one of the basic theories of biology.