Microscopy Flashcards
(9 cards)
1
Q
what is magnification?
A
apparent enlargement of a specimen
2
Q
What is resolution?
A
shortest distance between two objects can still be distinguished as two separate objects
3
Q
What some detail about light microscopy?
A
- modern light microscopes can get x2000 & x1000 is fairly standard
- limited ability to visualize bacterial components or distinguish between bacteria without doing something extra
4
Q
What some details about staining?
A
- Safranin and Crystal violet in the gram stain
- staining is related to cell wall thickness, will kill specimens
5
Q
What is Phase contrast microscopy?
A
- separates light going into specimen, creating more contrast between specimen and background
- good for observing smaller details such as motility
6
Q
What is fluorescence microscopy?
A
- fluorochromes that emit light of specific wavelengths when excited by light of different wavelength
- can be an external due, attached to a molecule such as an antibody or DNA probe
- can be engineered into genes and viewed in living cells
- good for internal cell structures?
7
Q
What is Electron Microscopy?
A
- scanning EM: to view exterior
- transmission EM: to view small internal structures smallest specimens
8
Q
Magnetostatic bacteria
A
- bacteria that will align with magnetic field (magnetosomes)
9
Q
Scanning probe microscopy
A
- “tip” can be a physical object or an electron cloud in scanning tunneling microscopy
