Refractive index is important because its differnt

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Unformatted text preview: ETA WHY IS N IMPORTANT? REFRACTIVE INDEX IS IMPORTANT BECAUSE ITS DIFFERNT FOR EACH SPECIMEN Phase contrast image ALIVE BRIGHT RING AROUND CELL IN WATER YOU CAN TELL DIFFERENCE BETWEEN CELL AND BACKGROUND BECAUSE LIGHT HAS BEEN BENT AND HAS BEEN SEPARATED FROM LIGHT IN BG IF LOOKING AT SOMETHING THAT IS ENHANCED OPTICALLY, IT IS USUALLY PHASE CONTRAST; LOOKING AT LIVING ADVANTAGE: NO NEED TO KILL OR FIX SPECIMEN TO ACHIEVE CONTRAST STAINED SPECIMEN: FIXED AND STUCK ONTO SLIDE USUALLY WITH HEAT OR CHEMICAL, ORG IS #DEAD, MOST OBS IN MICROSCOPY IS DONE ON STAINED SPECIMENS ALCOHOL CHEMICAL FIXAT. HEAT FIX Positive stain DARK CELL/LIGHT BACKGROUND CELL TAKES UP DYE Negative stain NEGATIVE STAIN: BACKGROUND TAKES STAIN SPECIMEN DOES NOT. SIMPLE STAIN! SPORE STAIN Differential stain MORE THAN ONE DYE STAINS SPECIFIC COMPONENT OF CELL SAME ORGANISM, DIFF MORPHOLOGY VISIBLE SPORE: RESTING STAGE VISBILE CAUSE CELLS ARE EXCITED BY UV LIGHT AND WE SAW IT EMITTED Fluorescence stain STAINED WITH FLUOR STAIN WHOLE CELL HAS BEEN STAINED OBS WITH SPECIAL MICROSCOPE COMMON APPLICATION: USE A "TAG" NUCLEOTIDE TAG OR ANTIB...
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