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Priest Athanasius Kircher Observation
The Jesuit priest, Athanasius Kircher, showed that maggots and
other living creatures developed in decaying tissues. This is important because it gives a sense of microorganisms and what they do. -
Hooke published Micrographia
Micrographia was the first important work devoted to microscopical observation. This is important because it showed what the microscope could mean for naturalists and scientist everywhere. -
Leeuwenhoek Letter to the Royal Society
Leeuwenhoek wrote a letter to the Royal society explaining that the particles he saw under his microscope were indeed living organisms in which he named "animalcules". This is important because we now have the knowledge that the particles he found were microorganisms (which he called ‘‘animalcules’’), including protozoa and other unicellular organisms. This information is still significant in science today. -
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Lazzaro Spallanzani
Lazzaro Spallanzani disapproved of the "spontaneous generation" theory. He is important because he and other researchers showed that an organism derives from another organism(s) and that a gap exists between inanimate matter and life which is now formulated as a basic unit in the cell theory. -
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Theodore Schwann
Theodore Schwann is important because he created a conclusion similar to Schleiden (except about animals) and 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 statement is especially significant because this principle is in the formation of cells. -
Recognition of the nucleus
The Scottish botanist Robert Brown was the first to recognize the nucleus as an essential constituent of living cells. This is significant in understanding the composition of the cell and how it works the way it does. -
Cell Composition in Plants
The botanist Matthias Jakob Schleiden (1804–1881) suggested that every structural element of plants is composed of cells or their products. This is important because it added botanical cells into the formation of the cell theory. -
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Creation of cell theory
The creation of the idea that the cell is the basic component of living organisms is the ground rule of the cell theory. This is important because it has helped many scientists over the years understand the importance of cells. -
William His's Nerve-Cell Idea
Swiss embryologist Wilhelm His put forward the idea that the nerve-cell body and its prolongations form an independent unit. He suggested that a separation of cell units might be true of the central nervous system. This is important because the nervous
system began to be considered, like any other tissue after this idea. -
Introduction of the Term "neurons"
Waldeyer introduced the term ‘‘neurons’’ to indicate independent nerve cells. This is significant because thereafter, cell theory as applied to the nervous system became known as the ‘neuron theory’.