Microscopy

What are the different types of light microscopy?

Bright fieldDark fieldPhase contrastDifferential interferenceFluorescenceConfocalTwo photon excitation

What are the different types of electron microscopy?

Transmission EMScanning EM

What is the typical size of a red blood cell?

7 - 8 micrometers

What is the typical size of an eukaryotic cell?

15- 50 micrometers

Which type of microscopy has the highest resolution?

TEM

What are common fixatives for light microscopy?

Glutaraldehyde - cross links proteins at amino groups and carbohydrates on hydroxyl groups

What are common fixatives for EM?

Osmium tetraoxide - cross links double bonds. commonly used to fix lipids in membrane Cryofixation - sample is rapidly frozen in liquid ethane

What are common stains for light microscopy?

Hematoxylin and Eosin. Hematoxylin is a (+) dye so it stains negative molecules like nucelic acids, glycosaminoglycans, and ribosomesEosin is a (-) dye so it stains positive molecules like extracellular fibers, and cytoplasmic filaments

Which dye stains lipids?

Sudan black

Which dye stains reticular fibers?

Reticular fibers (spleen and lymph nodes)

What are common stains for transmission EM?

Staining employs deposition of heavy-metal based compounds.Osmium tetroxide, uranyl acetate, lead citrate

What kind of microscopy lets you see living cells?

Phase contrastDifferential interference

What type of microscopy is usually used for thicker specimen?

Confocal microscopyTwo - photon microscopy

What kind of stain/coat does negative staining involve?

Uranyl acetate

What can you see with freeze fracture techniques?

Internal membrane structuresex: inside of extracellular layer vs inside of cytoplasmic layer