ExtraQuizLabExam3 Flashcards
Ex.14 UV Exposure and bacterial growth
the dimerization is confined within adjacent thymine residues on same ______.
intrastrand
Ex.14 UV Exposure and bacterial growth
______ affects growth by interfering with DNA, resulting in thymine dimer formation.
UV light
Ex.14 UV Exposure and bacterial growthh
________ have consequence on DNA function including interference in DNA replication, transcription etc, so UV exposure of cells can lead to lethal effects for bacterial multiplications.
Dimmer lesions
Ex.14 UV Exposure and bacterial growth
what are the 2 common mechanisms operates for repairing the UV induced DNA damage?
Light Repair and Dark Repair
Ex.14 UV Exposure and bacterial growth
In ______, an enzyme called photolyase cleaves cross-linked DNA caused by UV damage.
- only occurs in light-filled environment
- DNA photolyase is a light-activated repair enzyme that breaks thymine dimers (T=T), restoring original DNA sequence
light repair
Ex.14 UV Exposure and bacterial growth
In ______, use an enzyme called N-glycosylase to cleave cross-links in DNA. Specifically, N-glycosylase.
- can occur in light or dark environments
- repair enzyme cuts the damaged section of DNA from the molecule, creating a gap that is then repaired by DNA polymerase I and DNA ligase
Dark Repair
Ex.15 Antimicrobial chemical agents
The __________ represent a clear area surrounding the disk where microbes fail to grow.
Zone of inhibition
Ex.15 Antimicrobial chemical agents
generate hydrogen peroxide and phenol radical cation toxic form is the ________
Strong oxidising agent
Ex.15 Antimicrobial chemical agents
AgN03, will ____ protein
denature
Ex.15 Antimicrobial chemical agents
Since AgN03 denatures protein, the Oligodynamic action of AgN03 is the ability of _____ in minute concentration to kill bacteria cells.
heavy metal
Ex.15 Antimicrobial chemical agents
1% of _____ solution to clean eyes of new borns, which prevent neonatal ophthalmic gonorrhea
AgN03
Ex.15 Antimicrobial chemical agents
______ is based antimicrobial agent
OCl hypochlorite ion is oxidising agent
bleach + H2O is hypochlorous acid (HClO)
chlorine
Ex.15 Antimicrobial chemical agents
Phenolia is made of 2 _____ connected by a bridge
phenols
Ex.17 Coliforms and water quality test
Coliforms are ___1___ facultative anaerobes, non spore forming facultative rods which ferments__2__ generating __3__ and __4__(4 is trapped by durham tube)
- Gram negative
- lactose
- Acid
- Gas
Ex.17 Coliforms and water quality test
_________ are found in soil, rotting vegetation and inside gastrointestinal tract of animals
enterobacter aerogenes
Ex.17 Coliforms and water quality test
Fecal coliforms are presented by ______, are normally resident of gastrointestinal tract of animals and humans and are representative indicator associated with fecal contamination of water.
E.coli
Ex.17 Coliforms and water quality test
Detection of fecal contamination of water is mutistep process but in this lab we will be restricting to the first 2 processes of ______ test and ______ test
Presumptive test and Confirmed test
Ex.17 Coliforms and water quality test
________ test uses broth tube which the samples will be inoculated contains a small glass tube(durham tube) to trap the gas produced as lactose metabolism continues
Presumptive test
Ex.17 Coliforms and water quality test
______ test uses EMB plate is used to confirm presence of fecal coliforms which exclusively originates from fecal contamination of water
Confirmed test
Ex.17 Coliforms and water quality test
In EMB plate, ______ will form metallic sheen when the plates are observed under fluorescent light.
E.coli
Ex.17 Coliforms and water quality test
_____ colonies are typically large, pink colonies with a dark center, there may be slight trace of metallic sheen
enterobacter aerogenes
Ex.20 IMViC Test
_____ shows whether the organism is able to break down tryptophan(amino acid), its media is enriched in tryptophan from the peptic digest of casein(milk protein).
Indole test
Ex.20 IMViC Test
In indole test, tryptophan is broken down by _______ enzyme (secreted by some bacteria) and indole component is released in the media.
trytophanase
Ex.20 IMViC Test
Upon addition of ____ reagent, free indole reacts with _____ reagent components and forms red colored complex which floats on top of the media. which means indole is presence if red to pink color appears on top of the media.
Kovac’s reagent
Ex.20 IMViC Test
If tryptophan is broken down by trytophanase, indole is presence due to Ammonia(NH3) under go pyruvate (respiratory/fermentative) after incubated, Kovac’s reagent is added is indication of _______
peptone/casein
Ex.20 IMViC Test
______ contain dimethylaminobenzaldehyde amyl alcohol
Kovac’s reagent
Ex.20 IMViC Test
In indole test, if no visble color change on top of the slant, and the media maintaining yellow color is indicative of ______ meaning no breakindown of tryptophan amino acid and no tryptophanase enzyme secreted by bacteria.
negative result
Ex.20 IMViC Test
_____ test validates presence of stable, highly acidic products from glucose metabolism. The test is used to detect if bacteria are able to form stable mixed acids by the fermentation pathway.
Methyl Red test(MR test)
Ex.20 IMViC Test
_____ is primarily used to differetiate between bacteria that produces large amounts of acids from those that generates acetoin or butanediol.
Methyl Red test(MR test)
Ex.20 IMViC Test
In Methyl Red Test(MR test) acidity is determined by addition of methyl red, a pH indicator dye ____ at pH 4.4 or less
Red
Ex.20 IMViC Test
In Methyl Red Test(MR test) acidity is determined by addition of methyl red, a pH indicator dye turns ______ pH exceeds towards alkaline side at pH 6.0
yellow
Ex.20 IMViC Test
In Methyl Red Test(MR test) acidity is determined by addition of methyl red, ____ color is indicative of inconclusive result
orange
Ex.20 IMViC Test
A red coloration indicates resence of stable _____ end products and is Methyl Red postive.
acidic
Ex.20 IMViC Test
______ test determines presence of acetoin, an intermediate in butanediol pathway, is used to check if acid end products are further metabolized to form butanediol. Butanediol is non acidic and Methyl Red test do not provide the expected result.
Voges-Proskauer test
Ex.20 IMViC Test
In Voges-Proskauer Test, for detection of acetoin, 2 reagents are used, which are Reagent l is __1___ (VP-l) and followed by Reagents ll is __2___(VP-ll) This complex, inturns reacts with the peptone component of media and forms a red/wine colored complex which indicative of a postive test.
- Alpha naphthol (VP-l)
- KOH (VP-ll)
Ex.20 IMViC Test
In Voges-Proskauer test, if no color change or copper color is indicative of ______
negative
Ex.20 IMViC Test
__1____ test determines whether organism can use ___1___ in media, if provided as a sole carbon source. its used to differentiate between common intestinal bacteria(members of the Enterobacteriaceae)
Citrate Test
Ex.20 IMViC Test
In citrate media, citrate is transported inside cells due to activity of citrate permease. the media is originally _______ in color (due to the media;s neutral pH).
green
Ex.20 IMViC Test
In citrate media, if citrate is translocated inside and metabolized by bacteria, the media becomes alkaline and changes color to Prussian ______.
Blue
Ex.20 IMViC Test
______ is defined medium and used as a slant, it has a citric acid(sodium citrate) as sole C source. The medium contains ammonium ions as the sole nitrogen source. the pH indicator. The pH indicator is bromothymol blue. The results of inoculated tubes are compared to an uninoculated control
Simmons Citrate media Test
Ex.20 IMViC Test
E.coli is ___1___ in MR test and ___2___ to VP Test
- Positive
- Negative
Ex.20 IMViC Test
Enterobacter aerogenes is ___1___ in MR test and ___2___ to VP Test
- Negative
- Postive
Ex.23 Enteric bacilli
The ______ includes many gram negative rods which are mainly motile, non spore forming and have the ability to ferment sugars such as lactose, glucose, etc, with acid and gas production
Enteric bacilli
Ex.23 Enteric bacilli
______ use is to ensure bacteria are good and healthy and any change in media affected the growth or morphology of bacteria cells
nutrient agar
Ex.23 Enteric bacilli
_____ used to identify intestinal fermenters from non fermenters. its a complex media and functions both as a selective and differential media, since it helps select gram negatives from the gram positives.
Mc Conkey Media
Ex.23 Enteric bacilli
_____ contains glucose/lactose sugar, bile salts, crystal violet, sodium deoxycholate and a pH indicator (neutral red), extract, peptones
Mc Conkey Media
Ex.23 Enteric bacilli
In Mc Conkey Agar, the bile salts and crystal violet _____ growth of all but certain gram negative rods.
inhibits
Ex.23 Enteric bacilli
In Mc Conkey Agar, Glucose/Lactose sugar ferment acidic end product which lead to stable and unstable indication of __1____.
- Pink
- Peptone
Ex.23 Enteric bacilli
In Mc Conkey Agar, non fermentor grow on media source of Carbon, its metabolize the _______ component of media, that form yellow or colorless colonies as they do not use lactose. Ammonia generated in the metabolism of this organic compound pushes the pH above 6.8.
peptone
Ex.23 Enteric bacilli
In Mc Conkey Agar, _____ inhibits all Gram positive rods/cocci and gram negative cocci except gram negative rods
crystal violet
Ex.23 Enteric bacilli
______ is used to differentiate organisms based on their ability to hydrolyze urea using the enzyme urease.
Urea broth
Ex.23 Enteric bacilli
______ is a complex media and mostly pathogens belonging to the genus Proteus can be distinquished from other enteric bacteria using this media.
urea broth
Ex.23 Enteric bacilli
_____ is hydrolyzed to ammonia and carbon dioxide by bacteria that synthesize and secrete urease
urea
Ex.23 Enteric bacilli
Many Enteric bacteria can metabolize ___1___, however some can metabolize __1___ faster, such as Proteus.
- urea
Ex.23 Enteric bacilli
_____ contains urea, yeast extract, phosphate buffer and pH indicator (phenol red)
Urea broth
Ex.23 Enteric bacilli
In Urea broth, ____ hydrolysis to ammonia will overpower the medium phosphate buffer towards basic solution and increase the pH
Urea
Ex.23 Enteric bacilli
In _______, twenty four hours following incubation, the medium can distingquish between rapid and slow urea hydrolysis. thus the medium differentiates between rapid urease producing organisms from the slower urease producers.
Urea broth
Ex.24 Sources of infection
______ reveal microbes that are found on the surface of inanimate objects and how they can be transmitted to humans.
formites
Ex.24 Sources of infection
____ activity will demonstrate how effectively you wash your hands, effective hand washing is critical in clinical practice especially during surgical procedures.
handwashing
Ex.24 Sources of infection
Insect (vector) living organisms ___1__ transmission is passive tran on body parts and __2__ is active pathogen multiples inside the insect
- merchanical transmission
- biological transmssion
Ex.25 Pyogenic cocci
______ lab experiment is aimed to study morphology, biochemical characteristics and pathogenicity.
Pyogenic cocci
Ex.25 Pyogenic cocci
________ is a selective ad differential medium. it’s used for isolation and differentiation of pathogenic Staphylococcus aureus from the non pathogenic staphylcoccus epidermidis
Mannitol Salt Agar
Ex.25 Pyogenic cocci
_____ contains mannitol sugar, 7.5% salt and the pH indicator (Phenol Red)
Mannitol Salt Agar
Ex.25 Pyogenic cocci
In Mannitol Salt Agar, only pathogenic strains of _______ are able to ferment mannitol sugar and change color around bacterial colonies to a yellow halo, This is due to mannitol fermentation and acid formation which subsequently lowers pH sufficiently to change to yellow.
Staphylococcus aureus
Ex.25 Pyogenic cocci
In Mannitol Salt Agar, non pathogenic of ______ will grow but you will not see any halo around bacterial colonies. it grows due to carbon source that uses peptone.
Staphylococcus epidermidis
Ex.25 Pyogenic cocci
___1__ test confirms the presence of bacteria, uses a culture from the blood agar plate and is smear to a filter paper, placing a drop of ___1___ reagent, will appear purple color which indicates as postive. Moraxella branhamella common throat bacterium, members of the genus Neisseria are Positive and Staphylococcus epidermidis and aureus are negative.
- oxidase
Ex.25 Pyogenic cocci
_____ test is used in clinical labs to isolate and to indentify members of the genus Neisseria/gonorrea
Oxidase Test
Ex.4 Gram staining
___1___ are those that retain the purple/violet color of the primary stain and ___2__ are the ones that are decolorized and accepts the counterstain safranin color (pink color)
- Gram postive
- Gram negative
Ex.4 Gram staining
_____ is the dye which is applied initially during mutistep differential staining procedure; it mainly stains all cells equally
Primary stain (crystal violet)
Ex.4 Gram staining
The ______ is the mordant for gram staining, which an additive added to dye solution, to intensify the stain, it binds to the dye and makes it less soluble.
Iodine
Ex.4 Gram staining
_____ usually an organic solvent which washes off the primary stain
decolorizing agent or alcohol
Ex.4 Gram staining
_____ is the dye which is applied to impart a contrasting color to cells that dont retain the primary stain during various steps of differential staining procedure, contrasting cells are not responsive to primary stain.
counterstain or secondary stain
Safranin is used in gram staining
