Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Micro Microscopy
| Question | Answer |
|---|---|
| Resolution | amount of detail that can be seen, and the closeness two objects can be and still be distinguishable |
| Contrast | how distinct the specimen is from the background enhanced by staining specimen (+ stain) or background (- stain) |
| How is resolution altered to improve quality of image? | shorter wavelength= better resolution electrons have very short wavelengths use immersion oil! |
| How is contrast altered to improve quality of image? | Phase contrast microscope, and Differential Interference Contrast (Nomarski) Microscope |
| Basic function and use of Bright field microscope | Light passes evenly through specimen. Most commonly used type of microscope. |
| Basic function and use of dark field microscope | metal plate in condenser blocks direct light so specimen is viewed by reflected light, creating dark background. Used for viewing very thin bacteria or other unstained specimens |
| basic function and use of phase contrast microscope | Light that hits specimen gets refracted and slowed down. This changes the phase of the refracted light. Specimen appears darker compared to bright background. Good for viewing internal structures with slight contrast differences. |
| basic function and use of differential interference contrast (DIC, Nomarski) microscope | Light separated by Wollaston prism and polarized. 2 polarized light beams pass through specimen and recombine. Good for viewing protozoa so appear 3D. |
| basic function and use of fluorescence microscope | UV light hits fluorescently labeled specimen that emits light that is visible to see. Good for specimens stained with fluorescent dye. Attach multiple fluorophores to different antibodies. |
| basic function and use of confocal scanning laser | uses a pinhole to shut out light from all but one plane of object. Images from many planes build a 3D image on computer. Good for viewing thick specimens |
| basic function and use of Transmission electron microscope (TEM) | Electron beam transmits through specimen and magnets control the electrons. Good for seeing inside of thin specimens high resolution at high magnification. Can't view too long or damage specimen. |
| basic function and use of scanning electron microscope (SEM) | Electron beams scan across surface. Reflected electrons and xrays produce 3D image. High resolution and magnification of outside of specimen. |
| basic function and use of Electron cryotomography microscope | Multiple TEM images taken from different angles to produce an internal 3D image. Good for very high resolution of internal structures in 3D. |
| basic function and use of atomic force microscope | Probe scans across surface and deflects as it encounters electron clouds around atoms and molecules. Can see atoms. Can push atoms and molecules around on a surface. |
| Difference between simple, differential and negative stains | Simple: basic (+) dye attaches to (-) phospholipid head groups Differential: More than one stain used to distinguish between cells Negative: stains background not the cell. for things with no charge and clear but can't stain. |
| what microbial structures are visualized by each type of stain? | Simple: phospholipids Differential: Gram stain- thickness of peptidoglycan. pink=thin gram(-) purple= thick gram(+) Acid-fast: waxy coating or not. red=acid fast blue=not Negative: for things with no charge and clear but can't stain |
Created by:
741750252
Popular Biology sets