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Antoni Van Leeuwenhoek
In 1660 he saw under his microscope were motile particles and solidified that these particles were indeed living organisms, which he called ‘‘animalcules". This is important because it contributed to the first evolution in anything cell related. -
Micrographia Published
Hooke published his book Micrographia in 1665. In this he described the microscopic units that made up the structure of a
slice of cork. This is important because this and coined the term ‘‘cells’’ or ‘‘pores’’ to refer to these units within the cork, and set precedent for the name of cells. -
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Recognization of Nucleus
Robert Brown was the first to recognize the nucleus as an essential constituent of living cells. This is important because Brown recognized the general occurrence of the nucleus in these cells and apparently thought of the organization of the plant in terms of cellular constituents, which greatly contributed to Matthias Jakob Schleiden's theory. -
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Theodor Schwann
Theodor Schwann stated that “the elementary parts of all tissues are formed of cells” and that “there is one universal principle of development for the elementary parts of organisms. This is important because this principle is in the formation of cells. -
Achromatic microscopes
The 1830s achromatic microscopes were made by Joseph Jackson Lister. This allowed more precise histological observations. Also,
Improvements were also made in tissue preservation and treating techniques. -
Matthias Jakob
Matthias Jakob Schleiden suggested that every structural element of plants is composed of cells or their product. This was derived from Brown's discovery of nucleus in a plant cell. This is important because this greatly contributed to Theodor Schwann's theory and discovery about cells in animals. -
Pre-Existing Cells
Rudolf Virchow and Albert Kölliker showed that cells are formed through scission of pre-existing cells. This is important because this became the basis of the theory of tissue formation, even if the
mechanisms of nuclear division were not understood at the time. -
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Neuron Theory
Santiago Ramón y Cajal became the main supporter and indefatigable champion of the neuron theory. This is important because his neuroanatomical investigations contributed to the
foundations of the basic concepts of modern neuroscience. However, definitive proof of the neuron theory was obtained only after the introduction of the electron microscope. -
Oil Imersion Lens
The official introduction of the oil immersion lens happened in 1870 by Thomas Ross, suggested by Van Heurck. This is important because the development of the microtome technique and the use of new fixing methods and dyes greatly improved the efficiency of microscopy. -
Salamander Chromosome
Walther Flemming observed the longitudinal splitting of salamander chromosomes during metaphase and established that each half chromosome moves to the opposite pole of the mitotic nucleus.. This is important because it provided further evidence of the deep unity of the living world.