Question

MIcrobio lab final

_{_____________ enzyme reduces Nitrate to nitrite.}

_{Reduction is ____________ (loss or gain) of electrons}

_{In Nitrate reductions test- the source of nitrate is ________ (bacteria or medium)}

_{________ compound reduces nitrate to nitrite}

_{What is the chemical name of Nitrate I Reagent? ____________ _ _______________}

_{What is the chemical name of Nitrate II Reagent? ____________ _____________}

_{Explain (in 2-3 sentences) why the nitrate medium changes to red color after adding Nitrate reagent I and II to some cultures?}

_{Explain (in 2-3 sentences) why the nitrate medium changes turns clear after zinc to some cultures?}

_{The differential agent phenylalanine in Phenylalanine Deaminase test is _______________ (Sugar, or amino acid or protein)}

_{In the Phenylalanine Deaminase test the green color formed is due to the reaction between ____________ and ________________}

_{In BESC test the selective agent ___________ inhibits all Gram + bacteria except ____________}

_{In BESC test the differential agent ___________ is hydrolyzed to ___________}

_{In BESC test the indicator ___________ reacts with _____________ to form dark color}

_{The gas produced in KIA tube is due to A or B by bacteria.
A) sulfur reduction to H2S                        B)fermentation of sugars}

_{The black color change in KIA tube is due to A or B by bacteria.
A) sulfur reduction to H2S                        B)fermentation of sugars}

_{Describe how you will test and identify the susceptibility of bacteria to a specific antibiotic}

_{What is the other name for ‘Antimicrobial Susceptibility Test’?}

_{Describe briefly the steps in the above test?}

_{Mention at least 4 common antibiotic discs used in the above test.}

_{Give one example where the ‘Antimicrobial Susceptibility Test’ is used.}

_{In Lysine decarboxylase test mineral oil is added after inoculation to create ___________environment}

_{IMViC test purpose is to differentiate ____________ from ______________}

_{Expand IMViC__________________________________________.}

_{To MRVP broth what reagents are added for testing}

_{the production of mixed acids by fermentation _____________}

_{the production of alcohol or acetoin ___________________________}

_{Phenol Red media test for the ability of bacteria to metabolize ____________ sugars to ___________.}

_{Phenol Red media test tubes contain ___________ to test for the ability of bacteria to produce gas by fermenting sugars.}

_{Name two sugars used in Phenol red media: ____________ and ___________}

_{In SCA media the positive test shows __________ color change from __________ color.}

_{In Simmons citrate test release of ___________ increases the pH of the media}

_{Bacteria that contain _______________________ enzyme (removes carboxyl) will be able to metabolize lysine amino acid.}

_{In urea hydrolysis test the _________ color is positive for urea test}

_{Some bacteria can breakdown gelatin with the help of __________ enzyme they produce.
or
Some bacteria carry out gelatin _____________ reaction which is catalyzed by gelatinase enzyme which turns the media from _____ (state) to __________ (state)}

_{The gelatin media inoculated should be incubated at 25? C.}

_{Name the media used for identifying organisms that are motile by showing cloudiness throughout the tube
A) SCA            B)DNA media                       C) SIM            D)MRVP
or
In SIM media _________ indicates the presence of motile bacteria.}

_{____________ radiation causes thymine dimers
A. Infrared    B. Visible light                     C. UV                                     D. Microwaves}

_{DNA is damaged in bacteria exposed to harmful radiation but they recover by _____ DNA repair enzymes that require light}

_{DNA is damaged in bacteria exposed to harmful radiation but they recover by _____ DNA repair enzymes that do NOT require light
A. Exonucleases                  B. Endonucleases              
C. Photolyases                    D. ligases}

_{UV rays _______ pass through plastic and glass
A. Easily        B. Poorly       C. do not}

_{Transformation is the ability of bacteria to take up DNA from environmental phage.           A. True                                  B. False}

_{___________ and ___________ are required to make E. coli cells competent to take up DNA}

_{A. CaCl2 transformation solution and heat shock
B. LB broth and plasmid DNA
C. ice bath and water bath}

_{___________ gene is used for selecting the transformants.
A. Arabinose promoter     B. Ampicillin resistance
C. pGLO plasmid                 D. GFP}

_{___________ are small, naturally occurring, circular DNA molecules that possess few genes and ORI}

_{ChromosomesB. PlasmidsC. Genes}

_{GFP gene in the plasmid will be transcribed and translated in}

_{A. LB/amp plate +DNA                                        B. LB/amp/ara plate +DNA
C. LB/amp plate –DNA                                        D. LB plate–DNA}

_{“LB plate –DNA” allows growth of E.coli colonies which were not transformed.
A. True                                  B. False}

_{ELISA stands for _____}

_{List 2 advantages and one disadvantage of ELISA}

_{Results: Slide agglutinations shows ________ whereas ELISA shows_________ ______}

_{______ test is a simple procedure that is used to detect susceptibility to dental decay}

_{In _____ test, color change is an indicative of presence of dental- decay causing bacteria and _______ was used for sample.}

_{_______ sugar is used to favor the growth of oral bacteria}

_{E__________ is the study of diseases}

_{Determining the ______ _____ is the main objective of E______ simulation lab activity.}

_{Largest white blood cell (WBC) ____________}

_{WBC with 4-5 lobes ____________}

_{WBCs which are found in large numbers in normal blood sample _____________}

_{Presence of 6 Eosinophils out of 200 total WBCs counted is an indication of ____________.}

_{In a patient sample Number of Monocytes were 14%. What does this suggest}

_{Name the agranulocytes _____________ and granulocytes __________________}

   

Answer 1

Please ask questions separately and not all at once

Nitrate reductase

Gain of electrons

medium(this test checks the ability of the microbe to reduce nitrate from medium to nitrite )

Sulfanilic acid

N ,N-dimethylnaphthylamine

This test is based on the detection of nitrite in the medium formed by reduction of nitrate by microbe that is present. If present in the medium, nitrite will react with sulfanilic acid (Nitrate reagent A) to form a colorless complex (nitrite-sulfanilic acid). This complex forms a red precipitate (prontosil) with nitrate reagent B (alpha-naphthylamine).

Some strains may cause reduction of the nitrate to nitrite, and then to nitrogenous gases which are not detected when Nitrate reagents A and B are added to the medium. The zinc dust is a catalyst and catalyses the reduction of nitrate to nitritenitrite .If no color develops in the medium after the addition of zinc dust, the micorganisms may have reduced nitrite to nitrogenous gases; thus being nitrate-positive.