Unformatted text preview: wavelength of light is 400 nm. Show me how you calculate. Do not forget to write the units properly. ( 4 points ) 400nm/2X1 = 200nm or 0.2um 10. The reason why we use oil for the 100X objective is that the ( refractive index ) of oil is almost same with that of glass. ( two words, 2 points ) 11. 300 nm = ( 0.3 ) μ m (1 point ) 12. List the Gram Staining reagents and briefly define their roles ( 1-2 words maximum ) ( 4 points ) Sol I: 1% crystal violet we can stain the cell walls of both bacteria (gram + and gram -) Sol II: 2% iodine it is mordant. It makes bacterial cell walls hold the crystal violet. Sol III: 95% ethanol destain crystal violet. If you use this long, then even Gram+ bacteria will be destained as Gram – bacteria. Sol IV: 2.5% safranin it counterstains the destained bacterial cells....
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This note was uploaded on 08/24/2009 for the course BIO 126L taught by Professor Saxena during the Summer '08 term at University of Texas.
- Summer '08