Microbiology Lab Final Exam - Microbiology Lab Final Exam Pre-Midterm Material 3-11 3-8 Deptict amphitricous Spririlum 1 Morphology Rod with 3 coming

Microbiology Lab Final Exam - Microbiology Lab Final Exam...

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Microbiology Lab Final Exam Pre-Midterm Material 3-11, 3-8 Deptict amphitricous Spririlum 1. Morphology; Rod with 3 coming out Lophotrichous Rod 2. Clinical Significance of bacterial capsule-capsule indicates virulence 3. Why is heat fixing step omitted from capsule stain- because it shrinks the cell making it look positive for a capsule, 4. Capsule stain list Primary, Secondary and Decolorizer- primary stain:Congo Red, DC: Water, Secondary: Mannevals 5-4 Catalase 5. Reagent Added-h202 6. Positive or Negative result interpretation 7. Observation indicates 8. What are your conclusions 9. Example of poor specificity 15-6 Nitrate 1. List Observation-Red color produced 2. Conclusion-Nitrate is reduced to Nitrite 3. Purpose of 0.1% Agar in this medium-yield anaerobic environment 4. How might this observation change if KNO-3 omitted? -If KNO3 were omitted then NO3 wouldn’t reduce to NO2 so the color change wouldn’t be observed. 2-1,2-5 Ubiquity of Organism 1.Living things are composed of compounds from what fourbiochemical families? –Proteins, nucleic acids, lipids, 2.Define Ubiquitous-Grows everywhere3.Define Commensalism-one org benefits the other is 4.Given the ingredients list type of media ex. Defined or undefined? 5-7 Citrate 1. What inoculating Used-Needle
2. Inoculation Method-Streak no stab 3. Indicator in medium-Bromthymol blue 4. Result-the organism is positive 5. Conclusions from this test-the organism produces citrase. Section Five- Differential Tests Ex. 5-10, 15, 20, 22 & 23: BEA, DNAse, novobiocin, Taxo A, Taxo P, CAMP, BA, and Coagulase Streptococcal pathogens and Staphylococcal pathogens. Media used for the test and ingredients that make the test possible. Indicator and the end product of interest it detects. Relevant Observation, Result and Conclusion (ORC) GPC Flowchart MRSA & VRE 5-10 Bile Esculin Agar 1. Selective 2. Acid hydrolysis of esculin to Glucose and esculetin 3. Esculetin plus iron forms a dark brown color=positive test 4. Incubated at 35+- 2 degrees celcius for 24-48 hours 5. Ferric Citrate added as a source of oxidized iron to indicate + test. 6. Selective for gram negative enterics demonstrate tolerance to bile and members of streptococci. 7. Used to differ enterococcus from other gamma streptococci. 5-15 DNase Test 1. Green Top 2. May be used for Coagulase Negative organism. 3. Substrate-DNA
4. Indicator-Methyl Green 5. Plated on Minimal Media 2, 3 loops 6. Don’t read until you 2+ 7. Positive test when the orgn. Hydrolyzes DNA so green to colorless, Halo may be small 24-48 hours. 8. Differs Serratia(+) from Enterobacter, 9. Moraxella catarrhalis (+) from Neisseria species and 10. Staphylococcus aureus (+) from staphylococcus species 11. Forms Fragments 12. Dnsae from staphylococcus hydrolyzes DNA at the bond between the 5’ carbon and the phosphate, therbty producing fragments with a free 3 prime phosphate.

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