41⟩ Tell me who Invented Gram Stain?
Hans Christian Gram invented this stain in 1884. The original formulation was Aniline Gentian violet. Lugol’s iodine, absolute alcohol and Bismark brown.
Bacteriologist
Home Health Care Bacteriologist
“Bacteriologist Frequently Asked Questions in various Bacteriologist job interviews by interviewer. The set of questions are here to ensures that you offer a perfect answer posed to you. So get preparation for your new job interview”
76 Bacteriologist Questions And Answers
42⟩ Tell me how Is The Smear Graded?
Smears are graded depending on the number of bacilli seen
☛ 3-9 bacilli/entire smear: +
☛ 10 bacilli/entire smear ++
☛ 10 bacilli/in most oil Immersion fields: +++
43⟩ What is agglutination Reaction?
The process of clumping together, in suspension of antigen bearing cells, micro-organisms, or particles in the presence of specific antibodies called agglutinins. This leads to the formation of an insoluble immune complex.
44⟩ Explain me what Is Duckering?
Ducking Is a process of inactivation of Anthrax spores in animal products such as wool, hairs or bristles. It was introduced by Elmhirst Duckering, an enginer at wool factory. This is a live-step process. each lasting for 10 minutes and carried out at 40.5°c.
☛ immersion in 0.25-0.3% alkali
☛ immersion in soapy water
☛ immersion in 2% formaldehyde
☛ secondimmersion in 2% formaldehyde
☛ rinsinq in water
45⟩ Tell us what Are Chemisterilants?
These are the chemicals used for sterilization. They are 2% Gluteraldehyde (cidex). Ethylene Oxide (EO). Formaldehyde + steam and Beta — Propiolactone (BPL).
46⟩ Explain what Are The Articles Sterilized In An Autoclave?
Culture media, gloVes. cotton and clothes.
47⟩ Tell me which Are The Active Ingredients Of Commercial Mouthwashes?
The active ingredients include Chlorhexidine. Triclosan. Thymol. Cetylpyridinium Chloride, and alcohol. The composition varies across brands.
48⟩ Tell us how Is Air Sterilized?
By High Elliciency Particulate Air (HEPA) filters.
49⟩ Tell us what Are Metachromatic Granules?
Metachromatic granules are pol’ymetaphosphate reserves produced by Corynebacterium diphtheriae in nutritious medium. These granules are also known as Babes Ernst granules. ‘blutin granules. Polar bodies etc. They are called metachromatic granules because of they exhibit metachromasia.
a property where the granules appear in a colour different from that of the dye used When stained with polychrome methylene blue, they appear purple They are produced In abundance In serum containing medium such as Loeffler’s serum slope.
50⟩ Do you know why Are The Bacilli Arranged At Angles To Each Other?
The bacdh are arranged at angles to each other resembling English letter V or L or Chinese letter (cuneiform) pattern because the daughter cells doWt separate completely after cell dMslon (binary rission).
51⟩ Tell me how Is Operation Theatre Sterilized?
By fumigation with formaldehyde.
52⟩ What is allochthonous Flora?
Organisms that are not originally found in soil, but reach there by precipitation, sewage, diseased tissue and other such means. They do not contribute much ecologically.
53⟩ Do you know which Are The Alternatives Used In Gram Stain?
☛ Primary stain: Crystal violet. Methyl violet and Gentian violet
☛ Mordant: Grams iodine, rarely Lugols iodine
☛ Decolorizer: Alcohol, acetone. acteone-alcohol mixture (1:1)
☛ Counterstain: Dilute carbol fuchsin. safranin, neutral red. (Sandiford stain ror Gonococcj
54⟩ Tell us what Are The Various Modifications Of Gram Stain?
☛ Kopeloll’ and Beerman’s (Primary stain: Methyl violet. decolourizer: acetone or alcohol-acetone mixture 1:1)
☛ Jensen’s (Primary stain: Methyl violet, decolourizer: absolute alcohol. counterstain: Neutral red)
☛ Preston and Morrell’s (Primary stain: crystal violet. decolourizer: iodine-acetone)
☛ A.igert’s (Primary stain: Carbol gentian violet. decolourizer: Aniline-xylol). This is used to stain tissue sections.
55⟩ Tell me what is aerobic?
This includes organisms that require molecular oxygen to survive (aerobic organisms), an environment that has molecular oxygen, and processes that happen only in the presence of oxygen (aerobic respiration).
56⟩ Tell us how well do you work with people as Bacteriologist?
You work great with people! This question may stump you, but as a Bacteriologist, you may work on your own more often than in a group. The interviewer wants to hear that you work well with all types of people from patients to other health care professionals.
57⟩ Do you know what Do Albert A(1) And B(2) Solution Contain?
Solution A(1) contains Toluidine blue, Malachite green, Glacial acetic acid and Alcohol while solution 8(2) contains iodine and potassium iodide In distilled water.
58⟩ What is acetogenic Bacterium?
An aerobic, gram negative bacteria, that is rod-shaped, which is made of non-sporogenous organisms that produce acetic acid as a waste product.
59⟩ Tell us what Is Acid Fast Staining?
Certain bacteria or their structures have the ability to retain the primary dye (strong carbol fuchsin) and resist clecolourization by weak mineral acids such as H2S04. HCI. Such bacteria or their structure are termed acid fast and this property is termed acid fastness. There are two types of acid fast staining, the hot method and the cold method. The hot method (Ziehl-Neelsen) involves heating the slide while the cold methods such as Kinyoun’s and Gabbett’s do not involve heating the slide.
60⟩ Tell us what Is Acid-alcohol Decolourizer?
3% HCI in 95% alcohol (methylated spirit). This is useful in dilrerentiating saprophytic Mycobacteria from pathogenic Mycobacteria Pathogenic Mycobacteria are both acid and alcohol fast but saprophytic Mycobacterla are only acid-fast Saprophytic Mycobacterla can get declourized by alcohol. 95% alcohol can be used as a secondary decolorizer after decolourizing with acid Especially used in staining smears prepared from urine that may contain Mycobacterium smegmatis.
