Answer: 1) All the living organims are compound by one or more cells . 2) The cell is the structural and functional basic unit of life. 3) All cells are originated from other cells.
Explanation: Cell theory describes the characteristics of living organisms and was proposed and refined by many scientists like Schwann and Schleiden. The first principle describes the constitution of living organisms, all of them, unicellular or multicellular are compund by cells. The second principle says that cell is the unit of life in fuctions as metabolism and structural as in tissues. The third principle says that cells can only be generated by division of preexisting cells.