The cell theory was developed over a period of time by several scientists, primarily:
* Robert Hooke (1665): He was the first to observe and name "cells" while looking at a thin slice of cork under a microscope.
* Anton van Leeuwenhoek (1674): He was the first to observe living cells, including bacteria and protozoa, using his own microscopes.
* Matthias Schleiden (1838): He concluded that all plants are made up of cells.
* Theodor Schwann (1839): He extended the cell theory to animals, stating that all animals are also made up of cells.
* Rudolf Virchow (1855): He added the crucial component that all cells arise from pre-existing cells, summarizing the theory as "omnis cellula e cellula" ("all cells come from cells").
Janet Plowe was a biologist who made important contributions to the study of cell membranes and cell division, but she is not associated with the development of the cell theory.
