-
1st Compound Microscope
Zacharias Jansen makes the 1st compound microscope. -
Dead Cells Are Seen by Robert Hooke
Robert Hooke, and English scientist, discovered a honeycomb like structure in a cork slice using a compound microscope. He only saw cell walls as this was all dead tissue. The compartments looked like cellula, small rooms that monks lived in. So he named it cellula. -
Fist Living Cells are Seen By Leeuwenhoek
Anton van Leeuwenhoek, a Dutch biologist, looks at pond water with a microscope. He saw the first living cells, unlike Robert Hooke, who saw dead cells on a cork. -
More Microscopic Discoveries
Anton van Leeuwenhoek made several more discoveries on a microscopic level. Then he published a letter in the Royal Society which had drawing of what he saw. These was the first sighting of bacteria. -
First Sight of Cell Center
The center of the cell, the nucleus, is seen by Robert Brown. He had seen plant cells when he did this. -
Schleiden and Schwann State That All Plants Have Cells.
Matthias Jakob Schleiden and Theodor Schwann, German physiologist, proposed that all plant cells have cells, and that all plants are made up of cells. This was also the first generalized statement about cells. -
Two Parts of the Modern Cell Theory are Made
Theodor Schwann, another German botanist, concluded that animal tissue is also composed of cells. He also combined several cell statements and produced: 1. Cells are organisms and all organisms consist of one or more cells. 2. The cell is the basic unit of structure for all organisms. -
Braun Calls Transforms the Cell Theory
Carl Heinrich Braun transforms the cell theory by calling it the basic unit of life. -
Virchow Adds the Last Part of the Theory
Rudolf Virchow, a German physiologist/physician/pathologist added the last part to the cell theory. The Greek statement translates to "All cells develop only from existing cells." -
DNA Breakthrough
Miescher isolated DNA for the first time. -
First T.E.M. Demonstrated
The first Transmission Electron Microscope (TEM) made by Max Knoll and Ernst Ruska. A TEM uses electromagnetic lenses to focus the electrons in a thin light beam. This is what you see. -
Fist Commercial Electron Microscope
A scanning electron microscope (SEM) scans a focused electron beam over a surface to create an image. The electrons in the beam interact with the sample, producing various signals that can be used to obtain information about the surface topography and composition.
