A2.2 Cell structure SL Flashcards
Cell theory
All organisms have cells; cells form from existing cells.
Purpose of stains in microscopy
Stains highlight specific cell structures for visibility. Examples: iodine for plants, methylene blue for animals
Convert micrometers to millimeters
Divide micrometers by 1000. (1 mm = 1000 μm)
Magnification formula in microscopy
Magnification = Image Size / Actual Size
Steps for a temporary cell mount
Slice specimen thinly, place on slide, add stain, cover gently with a cover slip
Electron Microscope
A microscope that uses a beam of electrons to create an image of the specimen
Resolution of a light microscope
200 nm
Electron vs Light Microscope
Electrons have shorter wavelengths
Freeze Fracture Microscopy
Reveals internal structures by freezing
Cryogenic Electron Microscopy
Freezing improves resolution and reduces damage
Prokaryotic Cell
No nucleus, smaller size
Eukaryotic Cell
Contains nucleus, larger size
Prokaryotic Cell Size
Ranges from 0.1 to 5.0 μm
Ribosome Differences
Prokaryotes 70S, Eukaryotes 80S
Nucleoid
DNA region in prokaryotes