Question

the cell theory
these discoveries led to a fundamental concept of biology;
-- which states :

Explanation:

The cell theory is a fundamental concept in biology. It has three main tenets: all living organisms are composed of one or more cells; the cell is the basic unit of life; and all cells come from pre - existing cells.

Answer:

The cell theory; all living organisms are composed of one or more cells; the cell is the basic unit of life; all cells come from pre - existing cells