The English scientist Robert Hooke who used a makeshift microscope of his own invention to examine a variety of objects, including a thin piece of cork, made the first observations of cells in 1665. Noticing the rows of little boxes that made up the dead wood's tissue, Hooke created the term “cell” because the boxes reminded him of the small cells the monks in the monastery lived in. While Hooke was the first to study and describe cells, he did not realize their importance. At about the same time, the Dutch maker of microscopes Antoni van Leeuwenhoek prepared for the invention of one of the best microscopes of the time. Using his invention, Leeuwenhoek was the first to study, draw, and describe a lot of living organisms, including bacteria in saliva, one-celled organisms in pond water, and sperm. Two centuries passed, however, before scientists understood the true importance of cells. Modern ideas about cells appeared in the 1800s, when better light microscopes allowed scientists to observe more details of cells. Working together, the German botanist Matthias Jakob Shleiden and the German zoologist Theodor Schwann recognized the basic likeness between plant and animal cells. In 1839, they planned the new idea that all living things are made up of cells. During the 1800s, scientists began to understand some of the chemical processes in cells. Mullinax2In the 1920s, the ultracentrifuge was developed. The ultracentrifuge is a tool that spins cells or other things in test tubes at high speeds, which causes the heavier parts of the substance to fall to the bottom of the test tube. This device allowed scientists to separate the fairly heavy mitochondria from the rest of the cell and study their chemical reactions. By the late 1940s, scientists were able to explain the role of mitochondria in the cell. Using refined techniques with the ultracentrifuge, scientists subsequently isolated the smaller...
