Magnification=size of image/size of object (make sure units are the same)
Resolution- the power of a microscope to distinguish between two points
Cell Fractionation:
Homogenation- cells are broken, releases organelles. The resultant fluid (homogenate) is filtered to remove any complete cells/debris.
Ultracentrifugation- fragments in the homogenate are separated in an ultracentrifuge, which spins tubes of the homogenate at v.high speeds (needed to create a centrifugal force).
-gradually increase the speed
-next heaviest organelles forced to the bottom each time
-pelits: NMLERR (nucleus, mitrochondria, Lisosomes, endoplasmic reticulum, ribosomes)
e- microscope- e- beam has v.short wavelength so can resolve objects well
Resolution- the power of a microscope to distinguish between two points
Cell Fractionation:
- Cold-reduce enzyme activity, so doesn’t break down organelles
- Isotonic- prevent organelles from bursting/shrinking due to osmosis by making the water potential in the tissue and solution the same
- Buffered- maintain constant pH
Homogenation- cells are broken, releases organelles. The resultant fluid (homogenate) is filtered to remove any complete cells/debris.
Ultracentrifugation- fragments in the homogenate are separated in an ultracentrifuge, which spins tubes of the homogenate at v.high speeds (needed to create a centrifugal force).
-gradually increase the speed
-next heaviest organelles forced to the bottom each time
-pelits: NMLERR (nucleus, mitrochondria, Lisosomes, endoplasmic reticulum, ribosomes)
e- microscope- e- beam has v.short wavelength so can resolve objects well
Transmission e- microscope
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Scanning e- microscope
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