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MLT-Primary Tests
Microbiology
| Question | Answer |
|---|---|
| What is primary test? | Test/observation performed directly on bacterial colonies. Rapid demonstration of the enzymes or motility. |
| What are the colony morphology description? | circular, spindle, irregular, swarming(Proteus), mucoid(Klebsiella) |
| Oxygen condition for the growth of different type of microbes? | 1.Strict aerobe - only grow with O2. 2.Facultative anaerobe - can grow with or without O2. 3.Microaerophilic - only grow with 5-7% O2. 4.Strict anaerobe - only grow without O2. |
| _______ found in Gram positive rod only? | Spores |
| Spore forming bacteria are ______? | Heat resistant |
| How to stain spore forming bacteria? | Moeller's method, spores will be stained red by Carbol Fuchsin. |
| Another way to stain spore forming bacteria? | Malachite Green method, spores will be stained green. |
| What is the indirect method to test the presence of spores? | To test the survival of a culture after heating at 80 C for 10 min. |
| How to reveal the motility? | Hanging drop method or semi-solid agar. |
| How catalase test works? | A haemoprotein present in RBC that catalyses the breakdown of H2O2 to O2 and H2. |
| Catalase is used to differentiate ? | Staphylococci : + ve Streptococci: - ve |
| How Cytochrome oxidase test works? | Haemoproteins: transfer electrons to O2 in aerobic respiration. 1% tetramethyl p phenylenediamine di hydrochloride will be oxidized. Colourless to Deep purple. |
| Cytochrome oxidase test is used to test? | Pseudomonas aeruginosa: +ve Escherichia coli:-ve |