1320 HBL to get CP2078 (Sample Preparation for Microscopy)
Identity of learners
Admission Simply no
1 . Explain the principle of positive staining.
Positive staining is done simply by staining the cell wall surfaces of Gram-positive bacteria with crystal purple. The cellular wall of Gram-positive bacteria is made up of a thick part of peptidoglycan which undergoes dehydration during decolourisation triggering the follicles to shrink. This shrinkage of pores traps CV-I complex and stain the cell violet.
2 . By using a flow graph and or chart, outline the process of gram discoloration. (5 marks)
Flood the slide with crystal violet for you minute then rinse with water
Ton the slide with iodine for 1 minute then simply rinse with water
Overflow the slip with solution of ethanol and acetone for 15 to half a minute then rinse with normal water
Flood the slide with safranin to get 1 small then wash it with water
Blot dry the slide
several. What is the function of iodine once used in gram staining? (2 marks)
Their function should be to form significant crystals with crystal violet so that they stick to the bacterial cell wall and are not washed away very easily.
4. Affix photos about JPEG file format showing a gram great and gram negative microbe sample displaying their gram staining response. Give the identity of the microbe cells, forms and agreement. (9 marks)
Bacillus cereus: Rod molded and string arrangement, Gram positive /images/no_image.jpg
Neisseria gonorrhoea: Coffee bean designed and diplococcus arrangement, Gram negative /imgs/2019-08/60471439991_asdasdasdasd-article.jpg
5. Explain the rule of tablet staining employing both a and acidic dye. (5 marks)
Supplement staining with basic coloring is basically to stain the bacterial skin cells within the capsule without discoloration the outer part. Capsule discoloration with acid dye is to stain the...