The Cell theory

  • Jan Baptist van Helmont (15 century)
    1600 BCE

    Jan Baptist van Helmont (15 century)

    He recognized the existence of gases.
    Identified carbon dioxide.
    Photosynthesis
  • Zacharias Jansen
    1590 BCE

    Zacharias Jansen

    Invented the compound microscope
    End of the 16th century
  • Aristotle

    Aristotle

    -The author of the scientific and the philosophical system.
  • Robert Hooke

    Robert Hooke

    Discovered the law of elasticity. (Hooke’s Law)
    Did a ton of research for a variety of fields.
  • Anton van Leeuwenhoek

    Anton van Leeuwenhoek

    Research on lower animals contributed to the doctrine of spontaneous generation.
    Observations laid the foundation for the sciences of bacteria and protozoology.
  • Robert Brown

    Robert Brown

    Recognized the distinction between gymnosperms and angiosperms.
    Improved plant taxonomy.
    Contributed to the knowledge of plant morphology, embryology, and biogeography.
  • Theodor Schwann

    Theodor Schwann

    Schwann cells in the peripheral nervous system
    Study of pepsin
    Discovery of the organic nature of yeast
    Invention of the term metabolism
  • Matthias Schleiden

    Matthias Schleiden

    German botanist, cofounder of the cell theory.
    He wrote “Contributions to Phytogenesis” (1838), in which he stated that the different parts of the plant organism are composed of cells or derivatives of cells.
    Schleiden became the first to formulate what was then an informal belief as a principle of biology equal in importance to the atomic theory of chemistry.
    Recognized the importance of the cell nucleus.
  • Albrecht von Roelliker

    Albrecht von Roelliker

    Founded the “Journal of Scientific Zoology”.
    Kölliker’s investigations covered the development of cephalopods, structure of smooth muscle, and development and differentiation of red blood cells. The significance of the germ layers in development He described spermatozoa as cellular in origin and nature and emphasized the significance of sudden change in evolution as opposed to gradual change. Among his important works were “Handbook of Human Histology” and “Embryology of Man and Higher Animals”.
  • Rudolf Virchow

    Rudolf Virchow

    He pioneered the modern concept of pathological processes by his application of the cell theory.
    He emphasized that diseases arose, not in organs or tissues in general, but primarily in their individual cells.
  • Louis Pasteur

    Louis Pasteur

    One of the most important founders of medical microbiology.
    Contributions to science, technology, and medicine.
    Pioneered the study of molecular asymmetry.
    Discovered that microorganisms cause fermentation and disease.
    Originated the process of pasteurization.
    Saved the beer, wine, and silk industries in France.
    Developed vaccines against anthrax and rabies.