The Evolution of the Light and Electron Microscope

The birth of the optical microscope in the early 1000's, the first visual teaching material was invented (inventor unknown), it is called reading stone. It is described as a glass sphere magnifying a reading when placed on an object. Someone picked up a thick transparent crystal instead of the center, not the edge. And they took a look at it and noticed that it showed the object larger. In the 1st century AD, Roman philosophers Seneca and Priny's elders mentioned "Magnifying Glass", but at the end of the 13th century that glasses had never been used.

In the beginning of the 20th century, instead of optical microscopy, an important means of creating an image using electron beam instead of light was developed. In 1931, German physicist Ernst Ruska developed the first prototype electron microscope, transmission electron microscope (TEM) in collaboration with the electrician Max Knoll. Transmission electron microscopes function like optical microscopes, but at the position of the glass lenses, electrons are used instead of light and electromagnets. Higher resolution with electronics instead of light

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 magnify 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. The following 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 outside the structure and each lipid tail is in 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. Various parts of the membrane move continuously. This is why this membrane is liquid. This is called the plasma mosaic model of the plasma membrane.

Electron microscopes are different from optical microscopes. They play an important role in our understanding of cellular hyperfine structure. It shows us the detail details of the organelle. Electrons are used to create magnified images of cells. Since the wavelength of electrons is much shorter than the light, it has a strong resolution. Instead of the lamp used in the optical microscope, an electron gun is used to generate light, and then the electron gun is focused on the electromagnet. Since the dense area of ​​the electron creates a dark area, you can see the shape of the cell clearly. Dense electron beams can destroy parts of the tissue and create a brighter part of the image we see. After that, the resultant image is displayed on the screen or photo board. We call the obtained specimen photograph an electron microscope. The disadvantage is that the cells must be killed as the electron microscope can not be used to observe living cells