cell theory

  • Cell first observed

    Robert Hooke discovered a honeycomb-like structure in a cork slice using a primitive compound microscope.
  • First living cells seen

    Anton van Leeuwenhoek, a Dutch biologist, looks at pond water with a microscope he made lenses for.
  • Miniature animals

    Anton van Leeuwenhoek made several more 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 seen

    Robert Brown, an English botanist, discovered the nucleus in plant cells.
  • Basic building blocks

    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. This statement was the first generalized statement about cells.
  • 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
  • where does life come from

    Albrecht von Roelliker discoveres that sperm and eggs are also cells.
  • Basic unit of life

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

    Rudolf Virchow, a German physiologist/physician/pathologist added the 3rd part to the cell theory. The original is Greek, and states Omnis cellula e cellula. This translates as all cells develop only from existing cells. Virchow was also the first to propose that diseased cells come from healthy cells.