The work of Hans & Zacharia Janssen,
Robert Hooke, Anton van Leeuwenhoek,
Matthias Schleiden, Theodor Schwann,
Rudolph Virchow and others led to the
development of the Cell Theory.
They were father and son team who were Dutch
lens grinders. They developed the first
compound microscope.
Hooke was an English scientist. He looked at a thin
slice of cork through a compound microscope. He
observed tiny, hollow, room-like structures. He
called these structures “cells” because they
reminded him of the rooms that monks lived in.
Van Leeuwenhoek was a Dutch fabric merchant and
amateur scientist. He looked at blood, rainwater, and
scraping from teeth through a simple microscope. He
observed living cells and called some of them
“animalcules”. Some of the ‘animalcules’ are now
called bacteria.
Schleiden was a German botanist. He viewed plant
parts under a microscope. He discovered that
plant parts are made of cells.
Schwann was a German zoologist. He viewed
animal parts under a microscope. He
discovered that animal parts are made of cells.
Virchow was a German physician. He stated that all
living cells come only from other living cells.
The Cell Theory States:
• All living things are composed of cells.
• They are made of one of more cells.
• Cells are the basic unit of structure and
function in living things.
• Cells carry out all life activities.
• All Cells are produced from other cells.