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Cell Theory
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R. Hooke
Hooke made in discovery in 1665. Hooke used an early version of the microscope to look at a slice of dead cork. He saw, what seemed like, tiny compartments. This disproved the previous thought that living things just arose from some non-living matter. He contributed evidence that there are smaller organizations of life than organs and these smaller organizations are called cells. -
A. Leeuwenhoek
Leeuwenhoek's discovery happened in 1666. He used a single-lense microscope to analyze pond water. The magnification revealed an astonishing world of micro-organisms that seemed to be everywhere! Today these are known as bacteria! His observations solidified that cells are basic units of life. Leeuwenhoek proved that there are not only these different chambers but also single-celled organisms with different shapes that move around. -
R. Brown
Brown made his discovery in 1831.He contributed an addition to the cell structure, the nucleus. While investigating how plants fertilize, he discovered a structure within the cells throughout all of his trials. He continued to see these black dots and he came to the conclusion that they were in every cell and these became known as the nucleus. Brown disproved the misconception that cells are not just empty space. They contain structures within them like the nucleus. -
J. Schleiden
Schleiden's discovery was made in 1838. He contributed that all plant tissues are made of cells. Schleiden was a German botanist and so he used a microscope to look at different parts of a plant. When he did, he found that there were plants are also made up of cells. His discovery proved that plant tissues are made up of cells too. Not is it only just humans and human by products but also plants. -
T. Schwann
Schwann made his discovery in 1839.He contributed that animals were also made of cells. Following what Schliden discovered the previous year, Schwann decided to see if the same theory would apply to animals. He got a piece of animal tissue and looked at it under a microscope. The microscope showed that there were indeed cells however the cells were shaped differently. He disproved that all cells are the same shape, which was inferred. -
R. Virchow
Virchow's theory was made in 1855.He contributed that all cells are divisions of pre-existing cells. Virchow observed organisms to see that a whole organism does not get sick, only certain cells. Although an organism does get progressively sicker, so how could that be? He investigated and found that a cell divides to make more cells, thus the sickness spreads. He added to the previous theories that cells cannot just appear, they come from already existing cells and just divide.
