lab 5 &6 Micro Flashcards
5 categories of microorganisms
1) bacteria
2) virus
3) Protozoa
4) Fungi/molds
5) helminthes
is bacteria prokaryotes or eukaryotes
prokaryotic
are protozoa & fungi/molds prokaryotes or eukaryotes
eukaryotic
what does bacillus anthracis cause?
anthrax (Bacterial)
what does chlamydia trachoma’s cause?
chlamydia (bacterial)
what does clostridium perfringens cause?
food poisoning/gangrene (bacterial)
what does e.coli cause?
food poisoning/ UTI (bacterial)
what does mycobacterium tuberculosis cause?
tuberculosis (bacterial)
what does pseudomonas aeruginosa cause?
can infect burns/ wounds (bacteria)
what does staphylococcus aureus cause?
toxic shock syndrome or pneumonia (bacterial)
what does streptococcus progenies cause?
necrotizing fasciitis, scarlet fever, rheumatic fever ( bacterial)
what does varicella zoster cause?
chickenpox/shingles (VIRAL)
what does parmyxovirus cause?
mumps/measles (VIRAL)
what does rubella cause?
german measles (VIRAL)
what does herpes cause?
cold sores/genital sores (VIRAL)
what does rhinovirus cause
common cold (VIRAL)
what does influenza cause?
the flu (VIRAL)
what does epstein-barr virus cause?
mono (VIRAL)
what does human papillomarvirus cause?
genital warts/ cervical cancer (VIRAL)
what does norovirus cause?
gastro-enteritis/stomach flu (VIRAL)
what does plasmodium cause?
malaria (PROTOZOA)
what does toxoplasma gondii cause?
harmful to fetus’s (it’s in litter boxes) (PROTOZOA)
what does entamoeba cause?
amoebic dysentery (gut infection) (PROTOZOA)
what does guardian cause?
abdominal cramps & diarrhea (PROTOZOA)
what is saccharomyces cerevisiae found in?
its a fungus found in bread/beer
what is penillium found in?
a fungus found antibiotic/cheese
what is candida albicans?
a fungus from a yeast infection
what is trichophyton?
a fungus from athletes foot
what is pneumocystis jirovecil?
a fungus that causes pneumonia
what is crypto coccus neoformans?
a fungus that causes meningitis
what is stachybotrys chartarum ?
a fungus that causes upper resp. tract symptoms
what is a pathogen
organism capable of causing disease
examples of times when specimen collection is important
- sputum sample cannot have saliva
- urine may need to be midstream
- urine specimens must be refrigerated
- may need “holding medium” for bacterial survival
is macconkeys agar selective or differential
both
how is macconkeys agar differential
contains lactose, peptone & a colour indicator
what do the colours mean in macconkeys agar
red/pink=intestinal flora
white/colorless = pathogenic intestinal organisms
how is macconkeys selective?
components inhibit growth of non enteric bacteria w/ gram +, while permitting only gr- enteric to grow.
what is another name for culture & sensitivity test
kirby bauer test
what is the purpose of a streak plate
to isolate only a few bacteria in quad 4
what is an antibiotic
substance prevents growth of disease causing microorganisms
what is antiseptic
prevents growth of disease causing microorganisms
what is aseptic
free from microorganisms
what is bactericidal
substance that kills bateria (disinfectant, antiseptic, etc)
what is bacteriostatic
stops them from reproducing
what is incubation
provides optimal conditions for bacterial growth
what is colony morphology
-shape of colony w/ naked eye
-shape, edge, surface & elevation
umbonate = nipple elevation(LOL)
crateriform = inverted nipple (LOL)
what does coccus mean
round
what does bacillus mean
rod
what does spirillum mean
curved/coiled
what does diploids mean
2
what does strepto mean
chain
what does staphylo mean
cluster
how are gram stained cells classified by
cell wall (peptidoglycan or lipopolysaccharide over thin peptidoglycan)
what is special about lipopolysaccharides
the lipid in this area can trigger fever & shock
if a cell is purple…
it is rich in peptidoglycan (GRAM +)
if a cell is pink
it is rich in lipopolysaccharide (GRAM -)
what is heat fixing
kills bacteria & adheres it to slide
what does crystal violet do
stains peptidoglycan (especially gr +)
what does grams iodine do
forms insoluble complex with crystal violet (fixes the stain to the cell wall)
what does acetone-alcohol do
dehydrates cell, trap crystal violet/iodine complex
-in gr- it dissolves the lipoloysaccharide in outer membrane & washes away excess stain
what does safranin do
stains inner peptidoglycan coat of gr- and makes them pink
what are the steps of staining
water in circle, put bacteria on, beatrix, crystal V, rinse, iodine, no rinse, acetone-alcohol, rinse, safarin, rinse
what is a permissive agar
allows growth of any
what is an indicator agar
organisms not selected on basis of growth, but a compound of agar is altered by the bacteria so as to change the color of colonies & agar itself
what should be known about a blood agar plate
enriched media used to isolate organisms that require more nutrition
its a differential media used to detect hemolytic activity
what is B-hemolytic activity
will show a complete lysis of RBC (B CLEAR, CLEAR ZONE)
what is Alpha hemolytic activity
will show green partial lyse (A GREEN LYSE, A=GREEN)
what is y-hemolysis
no hemolytic activity
what is the macconkey agar designed to do
designed to grow gram - bacteria & stain them for lactose fermentation
On the macconkey agar: if its able to eat lactose
shows that it’s an enteric (gut) bacteria
what does MAC agar contain
- bile salts (inhibits non enteric)
- crystal violet (inhibit gram +)
- neutral red dye (stains microbes that ferment lactose)
- lactose
- pepton
what does MAC agar differentiate between
lac + and lac -
how will lac + look on MAC agar
(ex. Ecoli) it’ll produce acid which lowers pH. They will be RED/ PINK (they LOVE lactose !! so they’re pink)
how will lac- look
cannot utilize lactose so will use the peptone. Forms ammonia which raises agar ph. Colonies are white/colorless
what kind of a diagnosis is macconkey agar good for
diarrhea b/c it cane caused by salmonella or ecoli
salmonella cannot eat lactose
what does enteric mean
lives in gut
what does aerobic mean
needs O2 to grow
what does anaerobic mean
can grow without O2
what does pathogenic mean
causes disease
what would it mean in no colony on BAP
no bacteria or was somehow bile
colony on mac
gr - and is enteric
red = can eat lactose, white = cannot
white colony on mac=
gram - , enteric, cannot eat lactose
pink colony on mac=
gr-, enteric & lac +
no growth on Mac or BAP
no bacteria or killed
no growth on bap but some on MAC
contamination
factors for choosing an antibiotic
price, allergy, interactions, side effects & resistance
causes of nosocomial infections
not washing hands, improper use of antibiotics, unclean equipment
what are the impacts of nosocomial infections
3x longer hospital stay, death, lost limbs, disability
how to prevent nosocomial infections
hand wash, prompt catheter remove, PPE, aseptic technique
what is MRSA
methicillin resistant staphylococcus aureus (hard to treat)
what is VRE
vancomycin resistant enterococcus
hard to treat & can live a long time on objects
why are resistant bacteria so hard to treat
the antibiotics won’t work
