• In biology, cell theory is the historic scientific theory, now universally accepted, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells.

Hooke had discovered plant cells-more precisely what Hooke saw were the cell walls in cork tissue. In fact it was Hooke who coined the term cells the boxlike cells of cork reminded him of the cells of a monastery. Hooke also reported seeing similar structures in wood and in other plants.