Cell (biology)
Cells are units that are structured and functionally in all living organisms. Cells are the smallest units in one organism classified as living, and are often called live building blocks. Some organisms, like most bacteria, are unisel. Other organisms such as humans are the multiple cells The largest cell ever found is an unhealthy ostrich egg cell. In 1835 before the final cell theory was developed, Jan Evangelista Purkyně observed small "granules" when looking at the plant tissue continuously under the microscope. Cell theory, first developed in 1839 by Matthias Jakob Schleiden and Theodor Schwann, states that all the organisms are composed of one or more cells, of which all cells come from existing cells, the main functions of an organism occur within cells, and all cells contain important information for generations to organize cell functions and to send information to the next generation.