Chapter 9 summary (college+book) (Molecular Biology of the Cell)

Hoorcollege 9 - Lichtmicroscopie

cell = 10 micrometer
nucleus = 5 micrometer
mitochondrium = 0.5-1 micrometer
protein = 20 nanometer
atom = 1 Angstrom = 0.1 nanometer

resolutie van lichtmicroscoop = 0.2 micrometer = 200 nanometer

-> elektronenmicroscopie werkt alleen op dunne plakjes
-> lichtmicroscopie kan op levende cellen kijken
-> specifieke eiwitten kunnen aangekleurd worden met lichtmicroscopie

, phase contrast: witte laag om je cel heen!
darkfield: alleen het licht dat verstoord wordt vang je op




fluorescentie microscopie:
- photons (light particles) carry energy:
- shorter wavelength photons have higher energy
- wavelength corresponds with color
- energy levels (possible states) of molecules are discrete:
- only certain states are allowed
- absorption of photons can induced transitions to higher states (excitation)
- return to the ground state can be coupled to photon emission
- such emitted photons are always less energetic (red-shifted)

-> fluorescentie is dus photon in, photon uit -> maar energie gaat verloren dus wat dan
gebeurd is: blauw erin, groen eruit