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)