Modem cell theory is also known as cell doctrine or cell principle. This theory states that: (1) The bodies
of all living brings are made up of cells and their products. (2) Cells are the structural and functional units of living organisms. (3) Life exists only in cells
because all the activities of life are performed by cells. (4) Each cell maintains its individuality. It has a specific internal environment and homeostasis.
(5) Growth of an organism involves the growth and multiplication of its cell. (6) Genetic information is stored and expressed inside cells. (7) Life passes from one generation to the next in the form of a living cell. (8) New cells arises from pre-existing cells through division.