Summary
The Cell Theory is proof that every living thing on Earth contains one or more cells. It was officially articulated by Matthias Schleiden and Theodore Schwann in 1839 (Mallery). However, the first to study cells themselves was Robert Hooke. Hooke studied the cells using his microscope (Turner). He managed to study the cells on thin slices of bottle cork (Tavassoli). Cells are the unit of structure, physiology, and organization in living things (Mallery). The six modern tenets of the Cell Theory are: all known living things are made of cells, the cell is the structural and functional unit of all living things, all cells come from preexisting cells by division, cells contain hereditary information, all cells have similar chemical composition, all energy flow (metabolism and biochemistry) of life occurs within cells (Mallery). Most people don't think of cells as an important discovery, but without them, life would never have been the same.