Development of the Cell Theory

Events

Creation of the First Microscope

1590

Janssen created the first microscope. It had a 3x magnification but when extended, could reach up to 10x ("History of the Microscope", 2010)

Discovery of Cells

1663

Robert Hooke, studying thin slices of cork, discovered box-like structures he called "cells". They were called cells because the structure reminded him of the cells of a monastery("History of the Microscope", 2010).

Discovery of Unicellular Organisms

1674

Anton van Leeuwenhoek created a powerful microscope, and with it, discovered the existence of unicellular organisms.

Plants are made of cells

1838

Matthias Schleiden states that all plants are made of cells.

Animals are made of cells

1839

Theodore Schwann states that all animals are made of cells.

Cells come from cells

1855

Rudolf Virchow states that all cells come from preexisting cells.

Revolution of Optical Instruments

1886

Carl Zeiss, Ernst Abbe, and Otto Schott revolutionized the manufacture of optical instruments and invented the modern compound microscope.

Invention of the Electron Microscope

1931

Max Knoll and Ernst Ruska invented the electron microscope. With it, they were able to see even atoms.