Cell Theory

1.  All living things are made up of cells.
2.  Cells are the basic units of structure and function in living things.
3.  Living cells come only from other living cells.



Discoveries Which Led To Cell Theory

The Cell Theory was developed from three German scientist's discoveries. They are Matthias Schleiden, Theodor Schwann, and Rudolph Virchow.

In 1838 the German Botanist Matthias Schleiden discovered that all plants were composed of cells. Then only a year later a German zoologist, Theodor Schwann, discovered that all animals were composed of cells. Later in 1855 a German physician named Rudolph Virchow was doing experiments with diseases when he found that all cells come from other existing cells.

Cells of course were discovered much earlier. The first person to see a cell was Robert Hooke. He used a very primitive microscope, but when he was looking at cork cells under the microscope he saw cells for the first time. The shape of the cells reminded him of the monk monasteries and so he dubbed them "cells."

The first person to see living cells was Van Leeuwenhoek, a microscope builder.


The Cell Theory Timeline



Year of Discovery Scientist Contribution
1595 Hans and Zacharias Janssen produced the first compound microscope by combining two convex lenses within a tube
1665 Robert Hooke discovered the cellular composition of cork and introduced the word cell to science
1674 Anton van Leeuwenhoek improved magnification of microscopes by polishing lenses
1676 Anton van Leeuwenhoek "animacules" were discovered
1683 Anton van Leeuwenhoek discovered bacteria from a sample of saliva from his mouth
1838 Matthias Schleiden discovered the plants were made up of cells
1839 Theodor Schwann discovered that animals were made up of cells
1855 Rudolph Virchow stated that all living things come from other living things