The Invention of the Microscope

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1900 - present: In 1931, German scientists invented the electron microscope. Such a microscope directs the beam of accelerated electrons to a cell sample and when an electron is absorbed or scattered by different parts of the cell, they form an image that can be captured by the electronically sensitive photographic plate. With this model, scientists can see a very small part magnified 1 million times. The only drawback is that visible cells are not observed with the electron microscope. However, compound microscopes have been improved with digital and other new technologies, making it much easier for anyone to use microscopes, from children to laboratory microbiologists.

With the invention of the electron microscope, scientists opened up a whole new world. Most optical microscopes will magnify the sample 1000 times (1000 times), but the electron microscope will expand the sample more than 250,000 times! Using these microscopes, scientists can discover parts of unknown or unknown cells. The detail of the cell as seen with the electron microscope is called superstructure. Below is a diagram of a portion of the plasma membrane. Please note that they consist of phospholipid molecules and proteins. The phosphate head of each molecule is located outside the structure and each lipid tail is located on the inner part of the membrane. Protein location changes along the membrane. Please be aware that there are holes in the membrane. This is where the material enters and exits the cell. Part of the membrane continues to move. This is why this membrane is liquid. This is called the plasma mosaic model of the plasma membrane.