MICROSCOPY Tutorial 1 Types of Microscopy Light Fluorescence
- Slides: 19
MICROSCOPY Tutorial 1
Types of Microscopy • • Light Fluorescence Confocal Electron – Transmission Electron Microscopy (TEM) – Scanning Electron Microscopy (SEM)
LIGHT MICROSCOPY • Advantages – Live cells can be viewed, color can be seen • Disadvantages – Limit of resolution is 0. 2 microns • Organelles viewable – Nucleus, sometimes mitochondria and the Golgi apparatus
Light Microscopy cont. • Example: Onion epidermal cells. You can see the nucleus.
Fluorescence Microscopy • Fluorescent dyes (ie fluorochromes) (used for staining cells) are detected with the aid of a fluorescence microscope • Dyed objects show up in bright color on a dark background • Advantage – Can see live cells – Can highlight particular structures or molecules
Fluorescence Microscopy cont. • Example: DAPI stained to show DNA during cell division. • Top: (Interphase) Only the nucleus is visible • Bottom: (Mitosis) chromosomes lined up at centre of cell.
Transmission Electron Microscopy • Advantages – Good resolution (200 nm to 0. 2 nm; size from organelles to macromolecules • Disadvantages – Samples subject to electron bombardment and vacuum – Lots of sample preparation is required (fixation, resin embedding, sectioning into slices 50 -100 nm thick, heavy metal stain) – Hard to construct 3 -D structure from 2 -D slices – TEM cannot be used with living material
TEM cont. Example – Liver hepatocytes of a rat showing rough endoplasmic reticulum (RER) and mitochondria
Scanning Electron Microscopy • Advantages – Show surface structures – 3 -D images – Great depth of field • Disadvantages – Electrons require a vacuum so most samples have to be fixed and dried – Only topography (surface structure) can be seen
SEM cont • A male wolf spider • These teeth contain openings that release poison. They not only grasp the prey but immobilize it and inject it with poison.
Image Collection • The following slides contain images from the image database https: //www. biomedia. cellbiology. ubc. ca/cellbiol/ Can you tell what technique was used for each of the following images?
- Light sources for fluorescence microscopy
- Confocal fluorescence microscopy
- Bright field microscopy
- Fluorescence microscopy uses
- Laser confocal microscopy
- Light light light chapter 23
- Into the light chapter 22
- Light light light chapter 22
- Light microscope uses
- Light sheet microscopy
- Light field microscopy
- Types of microscopy
- Types of microscopy
- Beer's law fluorescence
- Relative fluorescence units
- Jablonski diagram
- Chemiluminescence vs fluorescence
- Principle of fluorescence spectroscopy
- Cold vapor atomic fluorescence spectrometry
- Cold vapor atomic fluorescence spectrometry