Answer:
All living things are made up of cells.
The cell theory is a widely accepted principle of biology. Scientists that contributed to the cell theory include; Theodor Schwann, Matthias Schleiden, and Rudolph Virchow.
The cell theory states that;
All living organisms are made up of cells and they may be unicellular or multicellular.
The cell is the basic structural and functional unit of life.
Cells arise from pre-existing cells.