Bac-T - Quiz 1-1

drraythe's version from 2015-06-08 23:06

shapes and their examples

Question Answer
Examples of cocci / shape?staphylococcus (bunches), streptococcus (lines) / round
Examples of straight rodsPseudomonas, e. coli
Examples of curved rods campylobacter, vibrio
Examples of branching rods Actinomyces, nocardia, dermatophilus (railroad tracks)
Examples of spirals Leptospira, borrelia
Examples of cocco-bacillary / shape?pasturella, multocida / very short/ ovoid rods
Examples of pleomorphic / shape?corynebacterium, / irregular shape
What are L-forms?No cell wall, mostly spherical
What cell has no shape?mycoplasma (not mycobacterium)

clicker questions

Question Answer
branching bacteria?actinomyces (also nocardia, dermatophilus)
what does placing a transport swab in the fridge accomplish?slows growth of bacteria
pink curvy rods on a would they react in the fridge?wouldnt grow
picture of gram positive rods "look like Chinese charaters" how would you describe it, what does it look like?pleomorphic, remember: corneybacterium
two major attributes of pasturellacoccobacilli and bipolar staining
does mycoplasma stain well with grams?no...mycoplasma doesnt have a cell wall to stain with grams
is tetanus contageous?no
endotoxins are secreted fromonly Gram negative bacteria
are penacillins bacteriostatic?no theyre bacteriocidal
is clavamox good to treat mycoplasma?no
exotoxins are produced by...gram positive and gram negative
does doxycycline affect gram neg bacteria?yes
are capsulated bacteria virulent?yes
what forms a spore and a capsule?bascillus anthrasis
no gram stain worked on a bacteria. what antibiotic would you use?tetracycline
what is the amount times (multiplied) the MIC (minimum inhibitory concentration) to treat something?3-5X MIC at target site
is clorhexadine sporicidal?no
what is an endotoxin?LPS's from the cell wall of gram negative bacteria
which is false? a. Penicllins inhibit cell wall synthesis b. Clavulanic acid is a beta-lactamase inhibitor c. Sulfonamides and trimethoprim should not be used together because of their antagonistic activity d. Antibacterial drugs are not effective against fungal infections e. Gentamicin is more likely to be effective against Psuedomonas than neomycin?C, sulfonamides
are transport swabs designed for bacteria to multiply when refrigerated?no

Review day + misc

Question Answer
what forms spores?bascillus anthrasis, clostridium tetani (bascillus and clostridiums all do)
corneybacterium would be described as?pleomorphic
what causes something to be stained gram positive?gram stain sticks on/into big layer of peptidoglycan of cell wall
what do you stain mycobacterium with?acid fast (wall too thick to use grams)
what do you use negative staining on, what is the stain?encapsulated bacteria....india ink
what do you stain leptospirosis with?gemsa or silverstain
what are pillishort adhesion filament
bipolar stain is what bacteria?pasturella
what does gram positive mean?peptidoglycans in cell wall (P as in positive)
what does gram negative mean?lipopolysaccharides in cell well (L as in loser as in negative attribute)
mastitis is caused byStaph(treat with clavamox) and Norcardia(treat with tetracycline, erythromycin, or Trimethoprim-sulfadiazine ) both cause mastitis and they are Gram + but E.Coli which is Gram Negative also can cause Mastitis and you treat with intramammary polymyxin
endotoxin is treated with?endotoxins produced by G- bact. treat with tetracylines and fluroquinolones since these treat gram negs and dont destroy the cell wall (endotoxins part of cell wall, released if destroyed)
what type of bacteria use pilli?gram negative (Pilli has lots of "L's" in lipopolysaccharides) (also gram positives wall is too thick for it) (pilli also look like little minus signs)
another name for pilifimbriae
examples of immune escapecapsules, toxins
aquisition of virulence factors (4)?mutation, transformation (entry of free DNA--set the transformers free!), transduction (via bacteriophage aka virus---duck! here comes a virus!), conjugation**(very common...donor gene. PLASMDS. conjugate to plasmidding).
what has outer membrane and periplasmic space?gram negatives (negatives have outer membrane for pili to attach to )
when is a guarded swab used?collection from uterus
florescent antibody test?antibody which fluoresces... if attaches to antigen, positive result will light up under blacklight. can test for antibodies (bruellosis) or antigens (black leg)
capsule is more common in what type of bacteria? example?mostly gram negative, but positives can too. example is streptococcus pneumoniae or pasturella (capsule wont "slide off" of gram negatives with their possible pili- also gram pos wall too smooth and big)
example of a bacteria using pilli in the intestines?E. Coli (they also have flagella)
what is e. coli's cultivation (doubling) time?20 min.
what is mycobacterium tuberculosis' cultivation (doubling) time?24 hours
anaerobic bacteria definition, and examples?requires NO O2 to grow. Fusobacterium, clostridia, ecoli (facilitative)
microaerobic definition, and examples?need a small amount of O2 (5%) ex: campylobacter jejuni (smiles in the sun--happy so dont need much)
aerobic definition, and examples?requires O2 to grow (20%). This is most bacteria.
psychrophilic definition, and examples?cold-loving (grow at 4*C) ex: listeria, (yersinia enterococlitica)
thermophilic defintion, and example?heat-loving (grow at 45* C) ex: campylobacter jejuni (smilin' in the sun)
how would you go about with sample collection?keep refrigerated to slow growth on collection media, don't use dry swabs (moist is what you want), anaerobes must be stored in anaerobic container.
hemolysis is evidenced on what agar? Example of this agar being used on _________?hemolysis = destroys blood in the BLOOD AGAR. staphylococcus does this. (gram negs and gram positives can be hemolytic, though)
how would you describe MacConkey agar?SELECTIVE (usually gram negatives but NOT gram positives grow on McC agar. I guess MacConkey like being a negative Nancy, ha.)
how is lactose fermentation indicated?pink colonies on McC agar
what color can pseudomonas be?pseudomonas will produce a green colony on McC agar.
what is a catalase test? what does it show?used to differentiate staph and strep. It is dropping 3% hydrogen peroxide onto a colony and seeing if it bubbles. If it bubbled, it's staph (positive test) [the staph and rod of the great catalase master!]
what makes a bacteria resistant to penicillin? example?if the bacteria produces beta-lactamase, it will destroy the beta lactam ring in the penicillin and render it useless. example is staph.
what is an agglutination test? example??serum of animal mixed with suspension of specific killed organisms. will "clot" if positive. example: brucella*
what is a tuberculin test? what type of a test is it? what does it test for?test for tuberculosis, it's a delayed hypersensitivity test. noteable reaction (swelling, irritation) to test means it's positive.
what is a mallein test? what type of test is it? what does it test for?it's a delayed hypersensitivity test. injecton into eyelid of horse. It diagnoses glanders' disease in horses. (swollen = positive test)
example of host susceptibility between species?shipping fever in cattle due to Mannheimia haemolytica does not affect dogs
what causes strangles in a horse?streptococcus equi.
example of a obligate pathogenbacillus anthracis (anthrax)
example of an opportunistic pathogen?E. coli in intestine/urinary tract, or a secondary pathogen moving in on infected area.
exogenous vs endogenous pathogen means what? examples?exogenous pathogen means infecting agent came from outside source of body. endogenous means from the body itself. Exogenous example = bascillus anthracis from the soil. Endogenous example = gingivitis in dog from commensals (symbiotic bacteria of the mouth)
example of a non-contagious pathogen?tetanus, or gingivitis
what is a secondary pathogen?only infects site after something else already has
example and explanation of attachment entry?E. Coli uses pilli to attach to intestinal mucosa and cause diarrhea. animal doesn't have immunity to pilli, so causes disease. only affects young because adults don't have receptors for the E. Coli.
what are some virulence factors (4)?pili, non-fimbrial adhesins, capsule, toxins
what bacteria can use entry via ingestion?salmonella from feed
what bacteria can use entry via skin abrasion or mucosa?leptospirosis from contaminated water "wiggle into" skin/mucosa
endotoxins are produced by? Examples?only gram negative bacteria.... examples include E. Coli, and salmonella. "endotoxemia" (endotoxins in blood) is/can be fatal
exotoxins are produced by? examples?both gram positive and gram negative bacteria.....example- tetanus neurotoxin, cholera toxin, E. Coli enterotoxin, botulism neurotoxin
4 major classifications of antibacterial drugs are?bactericidal, bacteriostatic, narrow spectrum and broad spectrum
example of bactericidal drugpenicillin
example of bacteriostatic drugtetracyclines
2 examples of narrow spectrum drugsbacitracin( gram positive--mess with cell wall), penicillin G (tracing a narrow line around the letter G)
example of broad spectrum drugstetracyclines
4 major mechanisms of action for antibacterial drugsinhibition of cell wall synthesis, damage to cell membrane function, inhibition of nucleic acid synthesis or function, inhibition of protein synthesis
most active agent against pseudomonas?gentamicin (everything is "gentle" on pseudomonas EXCEPT "gentle-mycin") (it is an aminoglycoside)
two most sporicidal agents?formaldehyde and chlorine dioxide
quantitative test is, example?gives us a quantity we can use, i.e., minimal inhibitory concentration....(lowest conc. of drug to stop growth of bact.). example is broth dilution method, used to calculate doses for infections
qualitative test is, example?example is kirby-bauer (disk diffusion) method. place antibiotic disks on plated bacteria. zone of inhibition is measured and compared...see how susceptible bact is to that antibiotic.
major gram positives? (10)clostridia, actinomyces, bacillus, streptococcus, staphylococcus, nocardia, rhodococcus, lysteria, corneybacterium, dermatophilus, (so...all of the branching ones. staph and strep. the two major spore forming ones. the psychophile, the pleomorphic one. and then the "rotary phone" ) - need listerine after you eat corn
major gram negatives?E. coli, salmonella, campylobacter, pseudomonas, brucella, leptospira, pasturella, bordetella, mannheimia, haemophilus, (curvy rods, rods, spirals...bipolar is baddd, bleeding is baddd, boarding school sucks, cow disease...)
what two examples of bacteria are not gram positive or negative?mycobacterium (wall too thick), mycoplasma (no wall)
what would cause a gram positive to appear red/pink like a gram negative?old or dead cells don't stain blue anymore
acid fast stain stains bacteria what color?pink
components of bacterial outer envelope? (7)capsule, flagella, pili/fimbriae, outer membrane/LPS(gram neg only), periplasmic space, cell wall, inner membrane
If you try to culture an infection and it doesn't have growth, was there nothing there?no, because there can be viable but non culturable bacteria in the decline phase
how to preserve a bacteria?freeze dry, freezing at -70*C, freeze in liquid nitrogen -190*C
how to inactivate a bacteria?thermal inactivation/sterilization, chemical inactivation via formalin
what is an API test?analytical products inc....strip with multiple tests on it, so you can do them all at once
routine cultures done on what 2 plates?blood agar and MacConkey
what is an antibiotic sensitivity test?disk diffusion (kirby-bauer) test
what is latex particle agglutination good for?test for bacterial antigens...such as typing for streptococcus/ staphylococcus
what is ELISA? what is it used for?enzyme-linked immunosorbent assay -- tests for antibodies (lyme) or toxins (clostridium)
what is attenuation?process of diminishing virulence (vaccine strains)
horizontal vs vertical transmission?horizontal= spread from environment. vertical= from mother to offspring during pregnancy
what type of toxin is an enterotoxin? which toxin is a neurotoxin?both exotoxin.....targets GI tract/ targets nervous tissue
4 stages of bacterial growth? 1) lag 2) exponential 3) stationary 4) death/decline
can cats acquire clinical leptospirosis from dogs?no, cats are resistant to lepto
Name an important disease diagnosed by detection of antibodies, and one diagnosed by an intradermal test (DTH)antibodies: ELISA for antibodies for LYME. DTH= delayed type hypersensitivity= glanders or tuberculosis
Can the virulence of a bacterium increase during an epidemic?I'd imagine so...that is why it became an epidemic. probably some new DNA to use.
Endotoxemia is likely to develop in a cow from Mastitis due to Streptococci or E. coli?E.Coli because endotoxins come from gram negatives

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