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Hooke
Hooke used an early compound microscope to observe a nonliving piece of cork. When he did this, he saw thousands of what he described to be tiny empty chambers. He called these chambers cells since they reminded him of rooms. He discovered that cells exist. This improved from the previous model because before, no one knew that cells existed. -
Leeuwenhoek
He used a single-lens microscope that he created to observe pond water and other things. Leeuwenhoek discovered that in the pond water, there were tiny living organisms that were only visible microscopically. These tiny living organisms are known as bacteria and protozoa. This improved from the previous model because he made it clear that a cell is the basic unit of life. -
Brown
He made observations that small particles that ejected from grains of pollen executed a kind of continuous and jittery movement. He discovered that cells have a nucleus. Before this, no one knew that cells had a nucleus. -
Schleiden
He observed plants microscopically. When he observed plants, he found that cells make up all plant tissues and the basic building blocks of plants are cells. Schleiden made the first general statement about cells. -
Schwann
He conducted research based off of Schleiden's research on plants and their cells. Through this research, he discovered that cells do not only make up plants, but they also make up animals. Before this, people just thought that animals were completely different from plans and therefore, would not have cells. He also created the cell theory by putting 2 statements about cells into one theory. -
Virchow
To make his contribution, he researched the roles that cells play in the body and in disease. He discovered that cells can only develop from already existing cells and diseased cells come from healthy cells. The previous scientists either did not know how new cells were created, or how they thought they were created (such as Schwann's theory) was proven wrong by Virchow's research.
