Development of Cell Theory

  • Hans and Zacharias Jansen

    • produced the first compound microscope by combining two convex lenses within a tube.
  • Robert Hooke

    • an English scientist who discovered the cellular composition of cork and introduced the word cell to science.
  • Francesco Redi

    • an Italian physician who performed an experiment to see if rotting meat changed into flies.
  • Anton van Leeuwenhoek

    • a Dutch biologist who improved magnification of microscopes by polishing lenses.
    • was first to see and describe bacteria.
  • Lazzaro Spallanzani

    • an Italian biologist and abbot who tried several variations on the experiments done by John Needham.
    • he discovered that soup that was kept sealed did not contain micro organisms that appeared in soup open to the air.
  • Robert Brown

    • an English botanist who discovered the nucleus in plant cells.
  • Matthias Schleiden

    • a German botanist proposes that all plant tissues are composed of cells.
  • Theodor Schwann

    • a German botanist who reached the conclusion that not only plants, but animal tissue as well is composed of cells.
  • Rudolph Virchow

    • a German physiologist/physician/pathologist who added the 3rd part of cell theory.
    • proposed that diseased cells come form healthy cells.
    • stated that all living things come from other living things.
  • Louis Pasteur

    • demonstrated that micro-organisms only come from other micro-organisms.
    • repeated the soup experiment, determining that soup spoiled when exposed to air only if the air was not filtered or if the container had an opening allowing micro-organisms to enter.