> See also: > - [[CryoEM]] > - [[Fluorescence]] # Microscopy **Microscopy** is the field of using microscopes *to view samples and objects too small* to be viewed with the unaided eye. ## Optical Microscopy > - [[Optical Microscopes]] One of the simplest forms of optical microscopy is **bright-field micrscopy**, where illumination light is transmitted through the sample and the contrast is generated by the absorbance of light in dense areas of the specimen. The technique of [[Cellular Staining]] can be combined with optical microscopy to further analyze specific… ## Fluorescence Microscopy ![[Pasted image 20230426104735.png|300]] In **fluorescence microscopy**, a molecule (such as an *antibody or protein of interest*) is labeled with a *fluorophore* (such as green fluorescent protein (GFP) or dyes) that *fluoresces* under a *specific wavelength* of light. ### Live Cell Imaging >- [White Blood Cell Chases Bacteria](https://www.youtube.com/watch?v=JnlULOjUhSQ) >- [Immune Cell Migration in the Zebrafish Inner Ear](https://www.youtube.com/watch?v=Hz0VlUVjYfI) ## Electron Microscopy Electron microscopy can There are two major types of electron microscopy: - **Transmission Electron Micrscopy (TEM):** Beams directly penetrate substance - **Scanning Electron Microscopy (SEM):** A technique where an electron beam bounces off of a *gold-coated sample* > [!example]+ **Light vs Transmission vs Electron Microscopy** ![[Pasted image 20230426105732.png|500]] > [!example]- **SEM vs TEM Images of Coronavirus** > ![[Pasted image 20230426110402.png]] > - **Left Image:** Coronavirus attacking a cell (SEM) > - **Right Image:** Spliced image of coronavirus (TEM) ### Transmission Electron Microscopy (TEM) ### Scanning Electron Microscopy (SEM) Because specimens must be *coated in gold* before being analyzed via SEM, this technique is mostly restricted to *analyzing the surfaces* of samples - Useful for generating *3D images/models*