Microbiology Flashcards
gram (+) bacteria is what color & what does it indicate
purple, has thick cell walls
acid-fast stains are used for
mycobacteria (tuberculosis)
what are the 4 nonselective culture media
blood agar, chocolate agar, thioglycolate broth, sabouraud dextrose agar
which nonselective culture media grows most bacteria & fungi
blood agar
which nonselective culture media grows most bacteria, including haemophilus & neisseria
chocolate agar
which nonselective culture media is an enrichment broth for anaerobic bacteria
thioglycolate broth
which nonselective culture media is used for recovering fungi
sabouraud dextrose agar
MacConkey agar is selective for what bacteria
gram-negative bacteria
what amplifies single copies of viral DNA & is very useful for detecting retroviruses, herpesviruses, & papillomaviruses
polymerase chain reaction (PCR)
what is used to quantify the amount of DNA or RNA in a sample & is useful for quantifying the number of HIV genes in a patient’s blood
real-time PCR
what structure in bacteria is involved in antibiotic resistance
plasmids
how are symptoms from bacterial infections produced
by excessive innate, immune, & inflammatory responses triggered by the infection
are staphylococci & streptococci gram-positive or gram-negative
gram-positive (thick cell wells)
what are the most common gram-positive cocci
staph aureus, staph epidermis
strep pneumonia, strep pyogenes, strep viridians
actinomyces & nocardia are what kind of pathogens
gram-positive filaments
neisseria is what kind of pathogen
gram-negative cocci
which gram-negative bacilli causes purulent conjunctivitis & angular blepharitis
moraxella
what gram-negative bacilli is found in decaying plant material & stagnant fresh water
pseudomonas aeruginosa
hemophilus influenzae is gram ____ & can cause what that involves the eye
gram negative bacilli
causes orbital cellulitis
what is an enterobacteria that can contaminate CL solutions
serratia marcescens
what spirochete causes Lyme disease
borrelia burgdorferi
what kind of pathogen is treponema pallidum, what is it sensitive to, & what does it cause
spirochete, sensitive to penicillin, causes syphilis
what are the 3 tests used to diagnose syphilis
VDRL, RPR, FTA-Abs
which syphilis diagnostic test is specific & will remain positive even after treatment
FTA-Abs
what is the difference between VDRL & RPR
VDRL - detects non-treponemal antibodies
RPR - detects non-treponemal antibodies made against T. pallidum
why do mycobacterium require acid-fast staining
they have a lipid-rich cell wall that’s resistant against disinfectants, sterilization, heat & chemicals
is chlamydia a bacteria or a virus
bacteria that behaves like a virus
chlamydia trachomatis serotypes A-C cause _____ & D-K cause ______
A-C: trachoma
D-K: inclusion conjunctivitis
what causes symptoms in viral diseases
the immune reaction against the virus
what are the 3 things viruses consist of
viral genome (DNA or RNA), capsid (protein shell), lipoproteins (envelopes surrounding capsid in SOME viruses)
why are viruses obligate intracellular parasites
they depend on host cell’s biochemical machinery for replication
naked capsid allows a virus to
spread easily, survive GI passage, & resist dryness & detergents
enveloped capsid allows a virus to
spread through body fluids & organs
which virion type is suceptible to antibiotics
naked capsid
which virion type requires a more complex immune response
enveloped capsid
which virion type requires cell lysis for replication
naked capsid
which virion type causes more hypersensitivity reactions
enveloped capsid
where do viruses replicate
host’s nucleus or cytoplasm
describe the lytic life cycle
for naked capsid viruses → enters cell → transcribed → fills cell with capsid → cell bursts & releases the capsids
describe the lysogenic life cycle
virus inserts itself into host’s genome → gradually produces & releases viruses over time
which life cycle allows the host cell to survive longer & why
lysogenic → virus incorporates itself into the cell
the longer the host cell lives → the longer it can sustain infection
what are some viruses that use the lysogenic life cycle
HIV, herpes viruses
what bacterial element allows for transfer of DNA from one bacterium to another?
pili
