Development of Cell theory

  • Jan 1, 1540

    Andreas Vesalius

    When he was the chair of surgery and anatomy, he performed dissections on himself and made charts for his students from them. He then performed dissections on other humans and from his observations; he discovered that the animal’s anatomy is different to humans. He also wrote a book in 1543 called 'De Humani Corporis Fabrica' from his observations and human dissections, which made anatomy into a subject. He emphasised how studying the body structure is very significant in medicine.
  • Hans and Zacharis Janssen

    Zacharis Janssen and his father, Hans, were believed to be have invented the first optical microscope and a microscope with 9x magnification. He did this by putting two lenses in a tube. He is also believed to have created the first telescope in 1610, though this was only known in the Neverlands. Microscopes and telescopes were essential tools to discovering cells.
  • Robert Hooke

    Hooke was the first person to utilise the word "cell" to identify microscopic structures. He examined a slice of cork through a microscope and noticed the present of microscopic structures which he later named as “cells.” Through the examination of the cork, he was able to see the cell walls because corks were made from plant material. He used primitive microscopes to conduct his experiment and thus shows the development of the microscope over time. He was able to observe cell walls and drew his
  • Franceso Redi

    Franceso Redi was an Italian physician who conducted an experiment to test the hypothesis that rotting meat would turn into flies. He set up an experiment with two sets of rotting meat, one covered and another uncovered. He observed that only the uncovered meat showed the presence of maggots which later turned into flies. However through the results of the experiment, he proved that only flies could reproduce flies.Redi’s observations were significant to the development of cell theory as it disp
  • Anton van Leeuwenhoek

    The first man to observe and give detailed descriptions of bacteria, yeast plants, the circulation of blood cells, protozoa and other protists and sperm cells. He did so by grinding his own lenses and constructing relatively powerful microscopes (some of which achieved a magnification of 270 times). He made his discoveries by doing activities such as scraping some plaque off his own teeth and examining it under a microscope and seeing what he described as "little animalcules", which we now know
  • John Needham

    A man who strongly supported the idea of spontaneous generation. He conducted an experiment (which involved the heating of broth in tightly sealed flasks) and concluded that since microorganisms appeared immediately after the broth was cooled in an open container, it was a result of spontaneous generation. It was later found by Lazzaro Spallanzani that his experiment was not valid since the broth was not boiled long enough.
  • Lazzaro Spallanzani

    Lazzaro Spallanzani was an Italian Priest, and attempted to disprove spontaneous generation by conducting an experiment not dissimilar to that of Francesco Redi. John Needham, an English clergyman, showed that even after boiling chicken broth to kill microorganisms and sealing it, organisms appeared afterwards. Spallanzani was not convinced that this was spontaneous generation, and suggested that the microorganisms entered the air after it was boiled and before it was sealed. He modified the exp
  • Jean-Baptiste Lamarck

    Jean-Baptiste Lamarck was a French naturalist that was a major contributor to animal classification, the theory of evolution, and the development of the Cell Theory. He is largely accredited for the theory of inheritance of acquired characteristics, otherwise known as Lamarkism. He assisted in Schleiden and Schwann in the development of cell theory by stating that “. . . no body can have life if its constituent parts are not cellular tissue or are not formed by cellular tissue.” Hence, he helped
  • Lorenze Oken

    From his experiences as a naturalist looking at living animals lorenz speculated that all plants and animals were made up of tiny living “infusoria”. Infusoria to Oken were all the organisms that grew in plants and animals. This speculation of his, caused him to reject the spontaneous creation theory, (that living things suddenly appeared) thus furthering towards the modern day cell theory.
  • Robert Brown

    Robert Brown was a Scottish botanist who studied varies plant species in the eighteenth and nineteenth century. He discovered the cell nucleus in plants in 1831. However, he did not realise that cell nucleuses were present in all cells. During his expedition to Australia on the Investigator, he studied a collection of plant species. While studying orchids with his microscope, he found an ‘opaque spot’ within each cell. He believed that it was a key component of cells and gave it the term ‘nucleu
  • Matthias Jakob Schleiden

    Matthias Jakob Schleiden, a German botanist, investigated plants with a microscope as opposed to the botanists of his day that limited themselves to naming and describing plants. Through his investigations, Schleiden discovered that plants were made up of cells and that plant growth came about through the production of new cells which were propagates from the nuclei of old cells. His conclusion was that all plant tissues are composed of cells and plants were created and grew from a single cell.
  • Rudolf Virchow

    Rudolf Virchow was a German scientist who encouraged people to “think microscopically” and was known for coming up with the theory “All cells originate from pre-existing cells”, which was based on observations made by Schleiden and Schwann. This theory lead to one of his greatest achievements, that a whole organism does not get sick, but certain groups of cells, which contributed to medical research.
  • Louis Pasteur

    Louis Pasteur was a French chemist and microbiologist. Pasteur was known for founding the pasteurisation process as well as contributing to spontaneous generation by coming up with the ‘germ theory’. He was also first to demonstrate living things come only from other living things, by showing microorganisms would grow in sterilised broth only if broth was first exposed to air contained in reproductive cells. He also showed, although bacteria exist and spread everywhere, it can be controlled.
  • Theodor Schwann

    Theodor Schwann, a German physiologist, reached the same conclusion as Schleiden though his research was conducted on animal tissue, also conducted microscopically, not plant tissue. Schwann described cellular structure in animal cartilage, and pulled existing observations together into a theory with the concepts: 1. Cells are organisms and all organisms consist of one or more cells. 2. The cell is the basic unit of structure for all organisms and that plants and animals consist of the combinati