cell theory :: essays research papers

Cell TheoryThe Cell Theory states that all organisms argon unruffled of similar units of organization, called cells. The concept was formally articulated in 1839 by Schleiden and Schwann and has remained as the foundation of modern biology.Formulation of the cell openingIn 1838 Theodor Schwann and Matthias Schleiden were talking some their studies on cells. It has been suggested that when Schwann heard Schleiden describe plant cells with nuclei, he was stuck by the similarity of these plant cells to cells he had observed in animal tissues. The 2 published his bind on animal and plant cells the next year. Schwann summarized his observations into three conclusions about cells.1. The cell is the unit of structure, physiology, and organization in living things.2. The cell retains a dual creative activity as a distinct entity and building block in the construction of organisms.3. Cells form by free-cell formation, similar to the formation of crystals.We know today that the first two tenets are right, but the third is wrong.The cell theory include1. All known living things are made up of cells.2. The cell is structural and operational unit of all living things.3. All cells come from pre-existing cells by division.4. Cells contains hereditary information whish is passed from cell to cell during cell division.5. All cells are basically the same in chemical composition.6. All energy flow of life occurs within cells.With any theory, its tenets are based upon previous observations and facts. The cell theory is no different being founded upon the observations of many. For the first 150 years, the cell theory was just a structural idea. This stuctural view whish is found in just about text books describes the components of a cell and their fate in cell reproduction.