Cell Theory

1
Cell Theory

• 1590 Jansen invents the compound
• 1665 Hooke examines cork cells with an
  improved compound microscope
• 1650-1700 Leeuwenhoek (220x) observes
  unicellular organisms and nucleus.
• 1838 SheleidenAll plants are made up of
• cells (phytogenesis)
• 1839 Schwann (w/Shleiden) proposed the
• Cell Theory

2
Cell Theory

• 1840 Purkinje coined the term protoplasm
• 1855 Virchow showed that omnis cellula e
• cellula

3
CELL THEORY PRINCIPLES

• All organisms are composed of one or more cells,
  within which the life processes the metabolism
  and heredity occur.
• Cells are the smallest living things, the basic
  unit of organization of all organisms
• Cells arise by division of a previously existing
  cell Raven, P and G. Johnson Biology
  Third Edition. Mosby Year Book 1992.