The Cell Theory

  • The compound microscope is invented

    Hans Janssen and Zacharias Janssen invent the compound microscope. Which will help in the discovery of cells.
  • The Cell is observed for the first time

    Robert Hooke, an English scientist, discovered a honeycomb-like structure in a cork slice using a primitive compound microscope. He only saw cell walls as this was dead tissue. He called it a "cell" for these individual compartments he saw.
  • Spontaneous generation is disproved

    Francesco Redi, an Italian physician, did an experiment to determine if rotting meat turned into flies. He found that meat cannot turn into flies and only flies could make more flies. This helped to disprove the theory of spontaneous generation.
  • First living cells seen

    Anton van Leeuwenhoek, a Dutch biologist, looks at water with a microscope.
  • Bacteria is discovered

    Anton van Leeuwenhoek made several discoveries on a microscopic level, eventually publishing a letter to the Royal Society in which he included detailed drawings of what he saw. Among these was the first protozoa and bacteria discovered.
  • The center of the cell is seen

    Robert Brown, an English botanist, discovers the nucleus in cells.
  • Plant cells

    Matthias Schleiden discovered that plants were made up of cells
  • Statement about plant cells

    Matthias Jakob Schleiden, a German botanist, proposes that all plant tissues are composed of cells, and that cells are the basic building blocks of all plants.
  • The Cell theory

    Theodor Schwann, a German botanist reached the conclusion that not only plants, but animal tissue as well is composed of cells. This ended debates that plants and animals were fundamentally different in structure. He also pulled together and organized previous statement on cells into one theory, which states: 1 - Cells are organisms and all organisms consist of one or more cells 2 - The cell is the basic unit of structure for all organisms
  • More cells are found

    Albrecht von Roelliker discovers that sperm and eggs are also cells.
  • The new cell theory

    Carl Heinrich Braun reworks the cell theory, calling cells the basic unit of life.
  • 3rd part to the cell theory is added

    Rudolf Virchow, a German physiologist added the 3rd part to the cell theory. This says all cells only come from existing cells. Virchow was also the first to propose that all cells come from existing cells.