Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Maria_Micro_chp3
chp3
| Question | Answer |
|---|---|
| Environmental testing is very strict, selective differention for salmonella produces what? | -hydrogen sullfite |
| sythetic media | -contains pure organic and inorganic compounds in an exact chemical formula |
| pure culture | a container of medium that grows only a single known species or type of microorganism |
| Synthetic media: M9 medium (for E.coli) | -not expensive composition to grow (reason why we use it) -common source of sugar 1. glucose > as carbon source 2. ammonia sulfate > N source 3. KCl, NaCl, trace metals, thiamine |
| Complex media: nutrient broth | 1.Tryptone > amino acids 2.Yeast extract > vitamins,etc. 3. NaCl -tryptone and yeast extract are not chemically defined |
| physical state | -liquid media semi-solid media solid media |
| general purpose media function | -for growth of a broad range organisms, such as nutrient broth |
| chemical composition | -synthetic (chemically defined) and nonsynthetic (complex) |
| enriched media function | extra nutrients are added, for growth of fastidous bacteria; e.g. blood agar, chocolate blood agar, etc. |
| a bacterial colony was ________ into the broth medium and _________ at 37°C for 24 hours | 1. inoculated 2. incubated |
| functional types | general purpose, enriched, selective differential, anaerobic, transport, essay, enumeration |
| agar is not ___________ by most ____________ | 1. degradable 2. microbes |
| complex media | -contains at least one ingredient that is not chemically definable (such as animal extract)-general purpose |
| Physical states of media (examples) | 1.liquid:broth does not solidify 2.semisolid:clot-like consistency; contains a low amount of solidifying agent (agar or gelatin) 3.solid-firm surface for colony formation, usually contains 1.5% of agar |
| fastidious bacteria | -enriched media -lack metabolize capabilities -need this to grow -defines bacteria that require growth factors and complex nutrients |
| isolation | -separating one species from another |
| chocolate blood agar | -enriched media made by heating blood agar to burst looks dark so called this (causing pink eye) doctors office use this often |
| wound | expose a lot of nutrients to that |
| broths | liquid media are water-based solutions genetically termed this ex: milk, broths, infusion |
| _______ media contain a low percentage (.3-.5%) of __________, which can be used for ________ testing | 1. semi-solid 2. agar 3. motility |
| A _________ organism will grow throughout in the SIM medium | motile SIM: Sulfide- Indole- Motility- |
| What are the methods of culturing microorganisms? | 1.Pure culture 2.Growth media |
| _____ contain a high percent (1.5%) of ___________, which enables the formation of __________ | 1.solid media 2.agar 3. discreate colonies |
| agar | -a complex polysaccharide isolated from red algae, used as a solidifying agent (but not as a nutrient) -so stable no organism can hydrolyze it |
| agar provides framework to ___________ and _____________ | 1.hold moisture 2.nutrients |
| agar is _____ at room temperature and _________ at boiling (100°C) solidify at (42°C) | 1.solid 2.liquifies |
| _______(protein) can also be used as a solidifying agent (12%); but it can be digested by some bacteria that produce the ________ _________, which liquefies the media; used as a __________ | 1.gelatin 2.enzyme 3.gelatinase 4.diagnostic tool |
| What is the agar content in a typical solid agar plate? | 1.5% |
| What are the 5 I's of culturing microbes? | 1.Inoculation 2.Incubation 3.Isolation 4.Inspection 5.Identification |
| What are the three properties of culture media called? | 1.Physical state 2.Chemical composition 3.functional types |
| introduction of a sample into a container of media | Inoculation |
| a discrete growth that comes from one cell | colony |
| everything comes from original colony | pure culture of one species from cell |
| What are the three basic methods to obtain isolated colonies? | 1.Quadrant Streak 2.Pour Plate 3.Spreading |
| Staphylococcus | -live on skin -manitol salt agar plate selects for staphyloccus |
| differential agent of EMB plate | allows for differentiation of Lac+ and Lac- bacteria, with the help of the dyes |
| selective agents of EMB plate | -use 2 dyes which bind to change groups causing cell death at low concentration 1. eosin 2. methylene blue -select for gram negative bacteria in general |
| salt(S) | -.5% -inhibits most species that cannot tolerate salt, therefore selects for Staphylococcus species |
| differential media | containing differential agents which react different with different species -different colony colors |
| Which is the most dangerous S. aureus or S. epidermidis? | S. aureus because it causes wound infections and so forth |
| EMB plate, Strong acid producer is _________ (color here_______) | E. coli or metallic green sheen -lactose positive |
| Bile salts | -mixture of digestive juice -found in digestive tract at a concentration inhibit a bacteria to grow |
| selective media | -containing selective agents, which allow only one type of bacteria to grow (inhibiting others) |
| Mannitol salt agar: | purpose: for isolating staphylocci from samples (2 mechanisms) |
| Blood agar is also a 1.__________ bacteria exhibit different 2.__________(define) | 1. differential medium 2. hemolysin -any biological agent that is capable of destroying RBC and causing the release of hemoglobin |
| S. aureus | -most verent -drug resistant |
| ________ in media can distinguish 2.____(___) from 3.______(_____) bacteria | 1.lactose 2.Lac+ (lactose fermenter) 3.Lac- (non lactose fermenter) |
| selective agent and differential agent are used together or apart | -together |
| Blood agar contains_________ (amino acids) and _________(with_____RBC), used for __________ bacteria such as _________ | 1.tryptic soy 2.sheep blood (sheep) 3.fastidious pathogenic bacteria r. streptococcus |
| noncoliforms | -lactose negative or (gram negative) -don't produce acids nonpigmented because of background lavender color/light clear |
| Non E.coli coliforms | -lactose positive -dark color stain maybe dark puplish |
| MacConkey agar plates | -purpose:isolating coliforms (E. coli-like) -mechanisms: 1.Bile salt 2.Lactose |
| Lac+ (coliforms)color | dark red |
| Lac- (non-coliforms) color | white |
| lactose | -use sugar as differential system -disacharride -in order to use (heat) have organism split into 2 sugars -produce a lot of acid called colliforms |
| ______in plate inhibit most_______bacteria, allows________to grow | 1.Bile salts 2.gram positive 3.gram negative |
| a lot of disease are transmitted from fecal matter therefore look for with manual digestion called 1.___________ on 2._________ agar plates | 1.coliforms 2.MacConkey |
| ________medium contains a ________agent that absorbs oxygen or slows penetration of oxygen into medium; used for growing__________ and examples | 1.Reducing medium 2.reducing agent 3.anaerobic bacteria -e.g. FTM (fluid thioglycollate)medium -Brewer's anaerobic agar plates |
| top most _________ bottom least _________ can only grow on bacteria bottum | -oxygenated -anerobic |
| Miscellaneous Media | 1.Carbohydrate fermentation medium a)Acid b)gas -use sugar not only on plates but also on broth |
| What are two common fermentation products in bacteria? and define each (hint:production is detected and examples) | Acid and Gas Acid: production is detected by color change, inoculated starts with red color/ if use sugars turns to yellow color Gas-production is detected by gases collected in the Durham tube, gas formed by bacteria will go up and collect on top |
| by looking at gas and color can determine if bacteria___________ | is capable of using sugar |
| E. coli fermentation produce gas, acid, or both? | both |
| Wet mounts and hanging drop mounts | -allow examination of characteristics of live cells: motility, shape, and arrangement |
| fixed mounts | are made by drying and heating a film of specimen -this smear is then stained using dyes to permit visualization of cells or cell parts |
| What do dyes do? | -create contrast by imparting a color to cells or cell parts |
| 1 step in using staining technique | -kill bacteria -fix cells to slide don't over fix to change original shape |
| positive stains | -basic dyes (positive charge) are used, which binds to the specimen well -surfaces of microbes are negatively charged and attract basic dyes but not acidic dyes |
| negative stains | -acidic dyes (negative charge) that do not bind to the specimen, but rather around the specimen (the background) |
| simple stains | -one dye is used -positive stain type |
| differential stains | -two-different colored dyes one as the primary stain and another as counterstain to distinguish cell types or parts -positive stain types |
| EMB plate | purpose: isolating coliforms selects 4 gram negative bacteria |
| What does mannitol do to S. aureus and S. epidermidis? | S. auris can ferment mannitol and the acid produced can turn medium yellow S. epidermidis cannot ferment mannitol, colonies are white |
| a single visible colony represents a pure culture or single type of bacterium isolated from a mixed culture -process name | -isolation a single... |
| carbohydrate fermentation medium sugars | 1. sugars that can be fermented acids are produced 2. a pH indicator to show the reaction; basis for identifying certain bacteria and fungi |
| special stains | emphasize certain cell parts ex: capsule stain and flagella stain |
| basic dyes | cationic, with positive charges on the chromophore (when dissovle in water ionize and form positive change) Ex: methylene blue, crystal violet, etc. |
| an isolated cell multiplies to form a discrete _________ on________ | 1. colony 2. agar |
| mannitol (D) | -sugar not glucose / simple sugar -in the medium can differentiate S. aureus from other staphylococci |
| acidic dyes | -anionic with negative charges on the chromophere Ex: India ink, nigrosine doesn't stain cells but rather the background |
| Incubation | under conditions that allow growth (O2, temp., etc.) |
| differential stains examples | 1. gram stain 2. acid-fast stain 3. endospore stain |
Created by:
mjoyriegsecker
Popular Science sets