Matching Pairs 4.4 Cell TheoryOnline version History and Basic concepts of cell theory by Susana Montealegre 1 He said that all cells are produced by dividing existing cells. 2 Scientist who observed cells in cork for the first time. He calls them celle. 3 He was the first scientist to observe live microorganisms. 4 He said that all animal tissues are composed of cells 5 Postulate 3: All cells come from ________ 6 Postulate 1: All the organisms ..... 7 Postulate 2 The cell is the structural unit and the _______ 8 I conclude after studying plant tissues that all plants are made up of cells.