The History of the CELL

and the CELL THEORY

By Travis TerryCopyright © 2012 Travis Terry

What is a CELL?

The cell is the basic unit of structure and function in living organisms. There are many different types of cells, each with their own specific function, that act as the building

blocks of living organisms.

•Before the 16th century, cells were not known and scientists did not know that life was made up of any other matter…

•Towards the end of the 16th century, the Compound Microscope was invented which enabled many scientists to understand how life works from a different point of view. Scientists could now see objects that were much smaller than what the human eye alone could see.

•Without a few certain scientists, we would not understand how life works where we cannot see with our eyes alone. Eventually, the ‘Cell Theory’ was developed because of their work. Here are those people!

Meet the Scientists!

Both Hans and Zacharias Janssen, father and son, were Dutch lens makers who produced the first compound microscope.

1590

Hans and Zacharias Janssen

What is a compound microscope?A compound microscope is a microscope which

uses multiple lenses to collect light from the sample and then a separate set of lenses to focus

the light into the eye or camera.

The compound microscope is used to magnify extremely small objects.

1590 2012

Robert Hooke was an English scientist. He looked at a thin slice of cork through a compound microscope and observed tiny, hollow room-like structures. He called them cells, but only saw the outer cell walls because the cork cells were not alive.

1665

A sketch of Robert Hooke’s view of a sample of cork versus what cork can look like under a

microscope, magnified 1000 times.

Dutch amateur scientist; looked at blood, rain water, and scrapings from teeth through a simple microscope. He called these structures “animalcules”. These are now referred to as micro-organisms. He is commonly known as the ‘Father of Microbiology’.

1680

German botanist; viewed plant parts under a microscope and discovered that they are made of cells.

1838

1839German zoologist; viewed animal tissue from animal organs under a microscope and discovered that they were made of cells.

Theodor Schwann

Schleiden and Schwann

• The official fathers of the Cell Theory.

Robert Remack

• 1838 Discovered cell division

• He was denied full professor status due to his faith. Virchowplagiarized his theory a few yearslater.

1855German physician; stated that living cells come only from other living cells.

“Every cell comes from a cell.”

Rudolf Virchow

With the work of these people… the ‘Cell Theory’ was developed.

The ‘Cell Theory’ states…

•All living things or organisms are made of cells and their products.

•New cells are created by old cells dividing into two.

•Cells are the basic building units of life.