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The First Compound Microscope
In 1590, the first compound microscope was invented by Hans and Zacharias Janssen (a Dutch father and son team). Prior to the invention, the smallest thing that the average person could see with the naked eye was about the width of a strand of hair. The development enabled biologists of the late 16th century to magnify their specimen anywhere between 3x and 9x, later leading to many discoveries in relation to the ‘cell’ and cell theory. -
The First Use of the Term "Cell"
In 1665, Robert Hooke (a British scientist) made the breakthrough discovery that cork was made up of ‘cells’. Hooke used a microscope to examine a thin piece of cork (after being interested in its properties) and saw that the specimen was made up of small compartments that looked like jail cells. It also became apparent that cork could float because air was trapped inside of the cells. Subsequently, Robert Hooke used and introduced the term ‘cell’ to describe his findings. -
The Discovery of Microorganisms, Bacteria & Sperm
In 1677, Aton van Leeuwenhoek discovered that living microscopic organisms exist after examining a sample of pond water under a microscope. Leeuwenhoek observed small single-cell living creatures (protozoa) and named them ‘animalcules’, or what we know today as microorganisms. In addition, Aton discovered spermatozoa (sperm cells) from animals (insects, dogs, and humans), and crescent-shaped bacteria (genus selenomonas). -
The Discovery of the Nucleus
In 1831, Scottish scientist Robert Brown discovered that plants have a nucleus after studying the fertilisation mechanisms of orchids. He noted that it required pollen to create new plants and that ovals were present in plant cells that moved around. Brown realised that the oval was of great importance to the cells' reproduction process and named it the ‘nucleus’. This advancement also contributed to the idea that cells come from pre-existing cells. -
The Discovery of all Plants have Cells
In 1838, Matthias Schleiden discovered that all of the structural elements found in plants are made up of cells. The development was made when Matthias was microscopically analysing plants, and realised that all of the specimens were made up of small cells, made more recognisable by the cell wall. Further, Schleiden stated that the cell is the basic building block of all plant matter. -
The Discovery of all Animals have Cells
In 1839, Theodor Schwann concluded that all animals are made up of cells. Schwann used existing observations and agreed with Matthias Schleiden that; cells are organisms, and all organisms consist of one or more cells, and the cell is the basic unit of structure for all organisms. Theodor additionally stated that plants and animals are made up of combinations of these structures. This development led to two of the three focal principles of cell theory. -
The Discovery of all Cells come from Pre-existing Cells
In 1855, Rudolf Virchow made the breakthrough discovery that all new cells come from pre-existing cells by cell division; completing the cell theory. Virchow detailed that animals are unable to arise without previously existing animals; therefore, cells are unable to arise without previously existing cells. Although this idea originally came from Robert Remak (a neuroscientist), it became popularised by Virchow. -
The Invention of the First Synethic Dye
In 1856, William Henry Perkins discovered the first synthetic organic dye. Perkins named the dye ‘mauveine’, or what we know today as purple. The development occurred when Perkins was trying to synthesise a medication to treat malaria, after being unsuccessful, he rinsed out his flask and noticed that a solution formed with a purple colour. The revolutionary discovery led to microbiologists being able to identify cells in their specimen easier as they could now be stained. -
The Discovery of Mitosis
In 1878, Walther Flemming (a German biologist) discovered the cell division process known today as mitosis. The development was made when the biologist was studying the chromosomes within cells and made the realisation that cells divide, making him the first scientist to describe the process of mitosis and chromosomes. Further, the discovery contributed to cell theory and microbiology because it proved the theory of cells coming from pre-existing cells. -
The First Transmission Electron Microscope
In 1931, the first transmission electron microscope (TEM) was designed and built by Ernst Ruska and Max Knoll. The microscope used electrons rather than light like compound microscopes, enabling them to magnify the specimen up to 400x. The creation of the electron microscope assisted scientists in studying the parts and processes in the cell that could not be seen previously. -
The First Scanning Electron Microscope
In 1942, the first scanning electron microscope (SEM) was built by Ernst Ruska, after previously building the first transmission electron microscope (TEM). The SEM could transmit a beam of electrons across the surface of the specimen to provide even further clarity and magnification in comparison to the TEM. The objective of the significant development was to have an atomic resolution so that scientists could study atoms and other matter. -
The Discovery of DNA's Double Helix Structure
In 1953, deoxyribonucleic acid’s (DNA) double helix structure was first identified by Dr James Watson and Francis Crick, though, DNA itself was originally discovered by Freidrich Miescher in the 1860s. The advancement in molecular biology led scientists to better understand how DNA functions and how these genes control the processes within cells. Furthermore, the double helix discovery was integral in understanding the structure and importance of DNA. -
The Noble Prize for Microscopy
In 1986, Ernst Ruska, Greg Binning, and Heinrich Rohrer were all awarded the Noble Prize in Physics for their innovation and fundamental work in the field of microscopy. Ruska was recognised as the designer and builder of the first transmission electron microscope (TEM) and received one half of the prize, and Binning and Rohrer were acknowledged for their design of the first scanning tunnelling microscope (STM), receiving a quarter of the prize each.
