finals lesson 4 Flashcards
Mostsensitive indicator of postmortem
change
Mitochondriaand endoplasmic reticulum
➢ Usesaldehyde
○ Ex. glutaraldehyde
○ Stabilizesproteins
○ Effectiveat 1.5% to
primary fixation
➢ Usesosmium tetroxide
○ Retains lipids
○ Effectiveat 1% or 2%
○ Mustbe handled well because the sediments that can be form with this, can lead to blindness
secondary fixation
Osmiumtetroxide is used at what temperature
room temperature
what is the duration in 0.5-1 mm3 in 2.5% glutaraldehyde
2-6hrs
duration in 1% osmiumtetroxide
60-90 minutes
buffer of choice in fixation
phosphate buffer
Fixatives buffered at what pH
pH 7.2-7.6
Embedding material that is not miscible
with water
epoxy resin
Avoidacetone if tissue will be stained with ___________
uranyl acetate
Embeddingmedium of choice
epoxy resin
Cutonly with glass knives
semi-thin sections
➢ Needed if larger viewing areas are required
➢ Plasticsfilms from collodion, formvar, butvar
support films
➢ Silverto straw colored sections
➢ Collectsections with a grid immerse in the floatation fluid
ultra thin sectioning
Colorproduced in staining
shades of gray
