Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
8 Cards in this Set
- Front
- Back
|
Light Microscope - how does it work? |
Light shines through sample, through two lenses (objective and eyepiece). Combined effect =magnification. |
|
|
Light Microscope - prep and staining |
Prep- sectioning, fixation, staining, cover slip applied (on wet Mount-immersed in liquid-or dry) |
|
|
Light - staining |
Distinguish between structures. Eg: bacteria retain crystal violet and appear purple (gram positive) and others do not (gram negative). |
|
|
Magnification |
Extent to which the actual size of an object is enlarged into the image seen through a microscope. Mag=size of image / actual size of object |
|
|
Resolution |
The extent to which two objects can be distinguished as separate structures. More detail at higher res. |
|
|
Transmission electron microscope |
Electronic beams pass through specimen. Mag=up to x500000 Res= 0.5nm ¦high mag and res. Intracellular details can be observed. × expensive. Complex prep of samples. Black and white images. Artefacts. |
|
|
Scanning electron microscope |
Electrons reflected back from specimen and detected. Mag=up to x100000 Res=3-10 nm ¦high mag and res. 3D images. × expensive. Complex prep of samples. Black and white images. Artefacts. |
|
|
Confocal laser scanning microscope |
Light absorbed by florescent chemicals and radiated back from specimen. Laser produces light in which waves are all in same direction(so bright and focused). ×poor res ¦3D images. Non invasive, living tissue can be observed. |
