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221 Cards in this Set

  • Front
  • Back
What is macroscopic?
-able to see with the eye
What is microscopic?
-not able to see with the eye alone
-anything less than .2 nm in diameter (200um)
What are the 3 domains of life?
What are the characteristics of prokaryotes?
-no nucleus
-no membrane bound organelles
-have ribosomes
What are the characteristics of Eukaryotes?
-has nucleus
-membrane bound organelles
What are the characteristics of Archaea?
-cell wall NOT made of Murein, but phosoplipids joined by ether links (C-O-C)
-live in extreme environments
-not pathogenic
What are the characteristics of bacteria?
-cell wall made of Murein
-cell membrane composed of phosolipids joined by ester links (COO)
What is the oldest kingdom in since the dawn of time?
What are viruses?
-not included in any domain
-acellular (no cells)
-not living
-(infection agents)
What is the cell theory?
-the smallest unit of life is the cell
-needs cell membrane, cytoplasm w/ ribosomes, a nucleus or nucleoid
What is the study of phycology?
What is the study of mycology?
What is the study of protozoology?
What is the study of virology?
What is the study of bacteriology?
What is the study of medical microbiology?
-relationship b/t disease and micro-organisms
What is the study parasitology?
-protozoa, helminths, some insects (ones that transfer diseases-mosquitos)
What is the study of immunology?
-defense mechanism, antibodies, antigens, allergy/hypersensitivities
What is the study molecular biology?
-DNA/RNA sequencing
What is the study of microbial ecologist?
-how organisms act in the soil, or other habitats, carbon cycle, nitrogen cycle
What is the study of microbial physiologist?
-metabolic pathways, fermentations
What are decomposers?
-absorptive hterotrophs (saprophytes live off dead material or saprobes)
What are antibiotics?
-chemicals from micro-organisms that will kill or stop the growth of another micro-organism in small concentrations
What are "chemotherapeutic agents"/magic bullets?
-affects the pathogen but not the host
What are examples of chemicals and drugs we get from micro-organisms?
-acetic acid, alcohol, and insulin
What foods do we get from micro-organisms?
-cheese, bread, beer, wine
How are bacteria good research tools?
-have 1 chromosome, so easy to work with
What is spoilage?
-bacteria/fungi don't know the difference b/t good and bad
-spoil food, shower curtains, walls
What are the benefits of micro-organsisms?
-chemotherapeutic agents/ magic bullets
-chemicals and food are derived
-research tools
What are detrimental aspects of micro-organsisms?
-cause disease
What are light microscopes?
-microscopes that let you see up to .2 mm (200 um)
-uses visible light
How does light travel?
-in waves
-longer wavelengths have less energy
What are usually the 4 objectives in microscopes?
-100x= oil immersion
-40x=high power
-10x= low power
How do you view most bacteria and why?
-by staining them
-becuase most are clear
What is the maximum magnification of our microscopes and why?
-resolving power= .2mm (200um)
What is the equation for resolving power?
RP= wavelength/ 2 x NA
-NA= numerical aperture
What does oil do in oil immersion?
-increases resolving power
-NA get larger
-greater resolution
Which type of light gives the worst resolution?
-red light
-highest wavelength
What can be seen witha light microscope?
-algae, protozoa, yeasts, molds (easiest)
-bacteria (harder to see)
What is a dark field stop?
-object in dark field microscope that blocks light from going through the cdenter of microscope
-light goes in an angle
-increases contrast of slide
What is the appearance of the view in dark-field microscope?
-black when no specimen
-light bends when there is a specimen
-specimen shines
Whatwould you use a dark field microscope for?
-for organisms that are alive but difficult with a bright field microscope
ex.: treponema pallidum
-to decrease artifacts(shapes covered in stains) and see shape of specimens better
What does an annular stop do?
-in phase contrast microscope that allows ring of light to go through
What is the function of the phase-shifting element of a phase contrast microscope?
-focuses light
-advance light (speed up) to increase brightness
-retard light (slow down) to make darker
-focuses direct rays, but not incident rays (rays off to the side)
What is a phase-contrast microscope used for?
-live organisms
-unstained organisms
What is a flourenscence microscope?
-has a mercru vapor lamp (intense light source)
-exciter filter
-barrier filter
-flourescent dye
What is the excirer filter used for?
-filters out >400 um light
-ultraviolet light passes through
What is a barrier filter used for?
-filters out <500 nm light
-blocks out uv light
What is flourescent dye used for?
-absorbs electromagetic energy
-uses quaramine O (type fo dye that flourences yellow)
-makes wavelength longer (visible light)
What is a flouresence microscope used for?
-to view mycobacterium
What do mycobacterium do and how do you view them?
-causes tuburculosis
-has high lipid content (very waxy)
-doesn't stain well
-use acid fast stain and oil immersion to view
What is treponema pallidum?
-causes syphilis (STD)
-cork screw shape (spirochete)
-stains poorly
-shines in dark-field microscope
What is immunoflourenscence?
-a technique to view syphilis and strep throat by flouresence
-when antigen invades body, antibodies are produced
-antibodes can be labeled with dye (ex: antisyphilis- Ab + dye)
-stain gets on antigen and shines
What is a differential interferance contrast microscope? What is the field of view like? What is it used for?
-uses prisms to view specimens
-increased contrast
-3-D effect
used for live specimens
What is a transmission electron microscope? What is the appaearance of the field? what is it used for?
-be able to see electrons (wavelength .1-.2 nm)
-has condensor magnet
-appearance depends on density (more dense= darker)
-background is white
-1000X more mag. than normal microscope (RP= .0005 um)
-can view viruses, inside bacteria, and DNA/proteins
What is a scanning electron microscope? What is the appearance of the field? What are its uses
-RP= .01 um (10 nm)
-10x greater than normal micrscope
-see fig 3.25
-to see detailed images on the surface of specimens (eps. bacteria)
What is the normal classification of bacteria? why is it important?
-for names
-to group
-makes identification easy
-can see relationships b/t bacteria
-gives us control and helps us solve problems
What is the artificial clasification of bacteria?
-few easily reconizable characteristics
-good for ID, bad for relationships
Ex: whittaher puts all prokaryotes in Monera
What is the natural classification of bacteria?
-shows common ancestry
-ex. woese and domains
-archaea closly related to us
-bacteria is very old
What are grancilicutes in Bergey's Manual of Systematic Bacteriology 1st edition?
-Grancilicutes -thin skin, gram neg (E. coli, klebsiella)
What are firmicutes in Bergey's Manuel of systematic bacteriology 1st edition?
thick skin, gram pos
-ex streptococci
What are tenercutes in Bergey's Manuel of systematic bacteriology 1st edition?
soft skin, no cell wall, gram neg.
ex. mycoplasmas
What are mendosicutes in Bergey's Manuel of systematic bacteriology 1st edition?
-faulty skin, no murein
-ex. archea
What is the significance of Bergey's manual of systematic Bacteriology?
-monera was main kingdom
-divided into 4 divisions
-divisions were based on cell wall chemistry content wtih gram staining
What are cyanobacteria in Bergey's Manuel of systematic bacteriology 2nd edition?
blue/green, photsynthetic, fouind in water, produce O2
What are actinobacteria in Bergey's Manuel of systematic bacteriology 2nd edition?
gram pos w/o G + C ratio (lots of G +C in DNA)
What are firmicutes in Bergey's Manuel of systematic bacteriology 2nd edition?
-gram pos, low G+C ratio
ex: streptococci, straphylococci, bacillus, clostridium, and mycoplamas
What are examples of proteobacteria?
E. coli, klebsiella, Neisseria, and Richettsia
What are examples of Chlamydia?
-ex. chlamydia trachomatic (common STD)
What are examples of spirochetes?
-syphilis (treponema pallidum) and Borrelia (lyme disease)
What are the 3 basic shapes of bacteria?
-coccus- spherical
What are examples of coccus shapped bacteria?
-staphylococci (boils)
-streptococci (strep throat/ pneumonia)
-neisseria (gonorrhea, meningitis)
What are examples of bacillis shaped bacteria?
-bacillus anthracis (anthrax)
-clostidium (tetanus)
What are examples of spiral shaped bacteria?
-vibrio cholerae (one bend)
-spirochetes (triponemu and bocrelia)
What is the size of cocci shapped bacteria?
-1 um
What is the size of bacillus shaped bacteria?
.5 um x 2 um
What is the size of spiral shaped bacteria?
-.5 um wide
-1-14 um long
What is the glycocalyx?
-outermost layer of microorganisms( esp. bacteria)
-extracellular (non-essential)
-either a slime layer (very thin) or a capsule (very thick)
What bacteria have a slime layer as their glycocalyx?
What bacteria have a capsule as their glycocalyx?
-klebsiella pnumonia
-streptococcus pneumonia
-steptococcus pyozenes
-bacillus antracis
-haemophilus influenza
What is the chemistry of glycocalyx?
-polysaccharides, proteins, or both
How is the glycocalyx regulated?
-by genes
-envrionment can influence expression of genes (such as nutrition)
How do glycocalyx capsules appear in colonies?
-looks like mucus
How do glycocalyx slime layers appear in colonies?
-looks shiny, wet
How do capsules appear under the microscope?
-only visible through negative stain (stain everything other than the microorganism)
-don't stain well
How would you negativly stain klebsiella Pneumonia?
-smear indian ink on slide and slide is coated black
-organism is purple and capsule is visible as halo around organsism
How is the glycocalyx important in identification of bacteria?
-morphology (rod, cocci, spiral)
-gram stain (pos or neg)
-biochem. test (test for enzymes- goes to geus and species)
-serovar (serological variety, used today for antibiotic resistance, vaccines (not all), and specific ID
What is the function of the glycocalyx?
-sticky to allow bacteria to form microcolonies (to prevent drying out)
-protects from phagocytosis when colonized
-can stick ot other objects
-virulent (pathogenic)
-animate (host-helps to stick to you
-inanimate (catheter-can get picked up and spread)
What does streptococcus pyogenius do for its glycocalyx?
-produces hyalunamic acid that is a cement that holds cells together.
What is gram +?
When microorganism is stained, turns purple
What is gram -?
When microorganism is stained, turns pink
What is the gram stain for terchoic acid?
gram +
What is the gram stain for 0-polysacharides?
-gram -
What is the gram stain for lysine
gram +
What is the gram stain for daiaminopinelic acid?
gram -
What is the gram stain for murein? Thickness?
50-90% gram + (20-80nm)
10-20% gram - (10nm)
What is the gram stain for porins?
-gram -
What is the gram stain for second membrane?
gram -
What is the gram stain for periplasmic space?
gram + (thin)
gram - (thick)
What is the gram stain for yeast?
thick cell wall (gram +)
What is the gram stain for mycoplasma?
-no cell wall
Where is the muerin sacchulus?
-before outer membrane
What is the outer membrane made of? Function? Significances?
-made of lipopolysaccarides
-protects cell from some antibiotics, detergents, bile, heavy metals, dyes, and lysozyme
-toxic when broken up
What is the periplasmic space?
-space or are b/t cell membrane adn otuer membrane in gram - organisms
-muerin sacchulus is in it
What is the plasma membrane?
-first living part of cell
-protoplast is living part of membrane
What is the function of the plasma membrane?
-regulates what goes in or out of cell
-differentially permemable
What is the plasma membrane made of?
-made of phospholipids (glycerol and 2 fatty acids)
-condensatiion occurs for bonds to form
-has hydrophilic head and hydrophobic tail (amphipathic)
What are plasma membranes most important for?
What is cholesterol in the plasma membrane?
-sterol steroid
-found in animals, makes membranes tough
-mycoplasma needs cholesterol to toughen the cell b/c of lack of cell wall
-fungi have ergoserol instead of cholesterol
What is a nucleoid?
knwon as nucleus in humans- 46 chromosomes
knwon as nucleoid in bacteria- 1 chromosome
What are plasmids?
-extrachromosomal DNA
-has resistance genes (way bacteria become resistant to antibodies)
-humans have plasmids in mitochondria
What are flagella?
-not visible under microscope (too thin)
-used for mobility
-one piece of filament
-spins/rotates cell
What are flagella in eukaryotes?
-on sperm
-has many filaments in each flagella
-filaments move back and forth (undulating)
What are flagella in prokaryotes?
-10% of bacteria are mobile
-mycoplasma glides (no flagella)
-if bacteria are mobile, then they are virulent
What are fimbriae?
-not for mobility
-shorter and thinner than flagella
-both mobile and non mobile have these
What do E.coli use fimbriae for?
-to attach to the epithelial intestinal wall
-considered virulent/pathogenic
-used for adherance
-Neisseria does same thing to cause gonorrhea
What are pili?
-used for DNA transfer in cell
-conjugation (one bacteria sticking to another)
What are endospores?
-cell dies and releases spore
-spore produces vegetative cell
-used to survive adverse conditions (dryness, chemicals)
-common in bacillus (anthrax), clostridium (tetanus), spocosarcirae, coxiella burretii
What is a culture medium?
-what bacteria is being grown in or on
What is animate?
What is inanimate?
What is nonsynthetic complex?
-at least one ingrediant not chemuically defined
What is synthetic complex?
-chemically defined
What are autotrophs?
-make their own food
What vare heterotrophs?
-can not make their own food
What are hypotrophs?
-obligate parasite (needs live host)
What is a natural media?
-something from the environment
What is milk as a media? What is it used for?
-inanimate, non-synthetic, natural media
-when you make yogurt or cheese to the natural milk media
-used to grow heterotophs b/c milk contains organic compounds
What is a dead tree branch as a media? What is it used for?
-inanimate, non-synthetic, natural media
-can grow mushrooms (heterotrophs)
What is soil as a media? what is it used for?
-inanimate, non-synthetic, natural media
-can grow mushrooms (heterotrophs)
-can grow algae (autotrophs)
What are the advantages of natural media?
-might be the only media an organism will grow on
-some organisms are unculturable
What are the disadvantages of natural media?
-aren't chemically defined and aren't sterile
-used commerically, bad for lab work
What is hot water extract (tea infusion) as a medium?
-complex, nonsynthetic
What is BHI medium (blood/heart infusion?
-boil the brain or heart of cow
-all good nutrients and stuff are extracted and the liquid is filtered off
-you make a powder out of the good stuff and sell it
What are the advantages of Hot H2O and BHI meidum?
-sterlizes medium
-major type used clinically
-faculative parasites will grow on it
-ex. staphylococcu aureus
What is synthetic media used for?
-can be used to gorw autotrophs (sugar plus CO2 added with inorganic N)
heterotrophs (organic N,amino acids, and sugar added)
What are the advantages of synthetic media?
-chemically defined
What are the disadvantages of syntehtic media?
-not all organism wik,ll gorw on it, expensive (to isolate A.A.)
What is isolate for the use of general media?
-you want to iso,late an organism from the original environment an d grow in on a medium
-for org. in human- add sheep blood
-for soil organism- mix in soil from it's environment
-for marine org.-use sea salt with simlar composition
ex. blood agar, manitol salt agar, Macclonkey's media, EMB
What is differentiation in the use of general media?
-the organism will look differently or act differently on the type of medium
-test for enzymes
-use gram staun, morphology, and biochemical (enzyme) tests
What is blood agar medium?
-add sheep blood to BHI medium and make sure the blood stays red
-look for hemolysis
-can org. break down blood?
What is gamma hemolysis?
-organism can;t break gown blood
-medium stays red
-organism is non-pathogenic
What is beta hemolysis?
blodd is completly broken down
-clear zone around colony
-organism is pathogenic
What is alpha hemolysis?
partial break down of blood
-green area present around org.
-some pathogenic
What is Manitol salt agar?
-manitol is an alcohol and a sugar
-specifically designed for staphylococcus aureus
-bacteria can break down sugar and produces an acid by product
-media turns yellow due to the acid while the rest of trghe medium is red (from the phenyl red)
What is MacClonkey's Medium?
-contains lactose
-if bacteria break down, acid forms
-Eosin and Methylin blue leak out and a purple nulceated colony appears
What is selective media?
-you select for/favor for the gorwth of aprticular organisms (byadding something to the medium that favors it)
-it also selects against too
What is selective in Manitol salt agar? What can grow on this?
-salt is selective
-7.5% NaCl sol. (most org. live in .5%)
-staphylococcus aureus can grow in it
-manitol makes it differential, salt makes it selective.
What is MacClonkey's agar? What can grow on this?
-add bile to medium to gorw G- organisms (outer membrane protects them from bile)
-G+ should not grow because they ahve no protection from bile.
What is selective in eosin methylin blue agar? What can grow on this?
-dyes make it selective
-G- are resistant to one dye b/c of the outer membrane
-G+ shouldn't grow out
What is enriched media?
-media for organisms that are organisms are Gastidious
(difficult to grow out on another media)
What is chocolate agar? What grows on this?
-a brown agar
-blood is brown heated to the point it changes color
-haemophilas influenza bacteria grow on this medium
What is a liquefiable solid?
-BHI agar (agar is an extract from red algae)
What is the consistency of media?
-liquid: a "broth"
What is a BHI broth?
-there is no solidifying agent (no agar)
-it's what's used in culture tubes
-used when you ahve a pure culture
What is a liquediable solid?
-BHI agar (agar is an extract from red algae)
-BHI comes in powdered form
How do you liquidfy BHI?
-add 1.5% agar to it
-boil at 100 deg to liquidfy
-put in autoclave to get to 121.5 deg to sterilize
-solidify in plate at 40 deg
-can reliquidfy if heat to 100 deg
-used most in labs
-but once solid, can;t reheat w/t messing up media
Why can't you add blood agar to a liquidfyable solid?
-would turn brown (chocolate agar)
-useless for hemolysis test
Why is it good to liquidfy silica?
-can grow stuff directly on it
-good to grow autotrophs b/c silica is an inorganic source
What is animate media?
-alive, must be cellular
-used to grow hypertrophs
What is the herpes simplex?
95% of us have this, but no symptoms
-causes membranes to fuse (multinucleate)
What is the cytomegalovirus?
-type of herpes virus
-causes inclusion bodies (intranuclear)
What does the rabies virus do to a cell?
-casues cell to have "dark bodies" (Nagri bodies)
What are plaquing techniques?
-virus casues cells to lyse
-ex: polio virus
-if virus is near cell membrane (area is clear)
What are embryonated eggs used for as a media? What can you grow?
-can use duck, turkey, or chicken
-need to pass needle through shell
-har and not sterile
-can cultivate live viruses in while orgaisms as babies
-ex: flu, richettsiae, chlamydiae
What is an intact animal or plant used for as media? What can you grow?
-can culture virus in wole organism
ex: hepatitus B-grow in primate surface
treponema pallidum- grow in rabbits
-mycobacterium laprae- grow in armadillos and chimpanzees
Why is moosture required for culture medias?
-b/t 70-95% water
-bacteria are absorptive
-need to conduct diffusion
-heterotrophs like us
-use hydrolysis
Why is food in utilizable form required for culture medias?
-if growing autotroph -need inorganics
-if growing heterotrophs- need correct organics
What pH is required for culture medias?
-pH=7.0 for best culture
-can priduce acids or basis
-use buffers to balance
-ex. peptone
Why is sterility important for culture medias?
-need a sterile culture
-don't mix cultures
What injurious chemicals are required for culture medias?
-agar (comes form red algae)
-water (pure)
Why is tonicity important for culture medias?
when preparing a culture, should be hypotonic
-would make microorganism turgid
What is population growth?
-increase number of individuals
What is binary fission?
-to split in half
-each microorganism will produce 2 every 20 min
What is the lag phase?
takes time to start pop. growth
What is log growth phase?
-population doubles every 20 min
What is the stationary phase?
-carrying capacity of the environment
-can;t increase population
-ran out of food
What is log death phase?
-large number of individuals die, but some are still alive
What is the logarithmic growth scale used for?
-penicillin doesn;t work during log growth
-only lag phase
What is cultural emuneration?
-grow out cells
What is the advantage of cultural emuneration?
-count living cells
What is the disadvanage of cultural emuneration?
-takes time to get results
What is the colony count plating method?
-count every cell
-cells can form colonies
What si a colony forming unit?
-either a single cell or colony
Which colony plate is apporpriate for counting?
-25-250 colonies
What is the membrane filter technique?
-uses filter paper with holes at .2um
What is the advantage of using the membrane fitler technique?
-viruses can still pass through
-bacteria get stuck on filter
-grows into colony in 24 hours
What are the disadvantages of membrane filter technique?
-can clog up if heavily contaminated
-only good for low loads
What is the Most Probable Number?
-not counting ind. cells
-used for coliforms (E.Coli)
-gets standardized w/ serum dilution
Whata re coliforms?
-G(-) rod that can ferment
What is the advantage of nin-cultural enumeration?
-quick results
What is the disadvantage of non-cultural enumeration?
-count live adn dead and artifacts
-count will be higher
What is cytometer count?
-uses peiroff houger counting chamber
-uses 1cm^2 of square to count
-glass is expensive
-can calculate volume
What is a coulter counter?
-uses electric beam to count cultures
-very accurate
What is the total volume used for in microorgansim count?
-used for beer (yeast)
-can standardize w/ cytometer count and colony count plating method.
What is the turbidometric used for?
-uses spectrophotomter
-tests how cloudy solution is
-cludier solution higher bacterial density
-standardize using cytometer count
What are variations?
-change in charactgeristsics
-either in an organism or a parent
What is phenotypic variation?
-temporariy changes in organism
-change in gene expresson
-not a mutation
What is morphological phenotypic variation?
-cell large when young
-gets smaller as get older
What is an example of cultural phenotypic variation?
-seratia marcescenes (G- rod)
37 deg.- white
25 deg.- red
-color change based on temperature
What is an example of physiological phenotypic variation?
E. coli
-has B-galactosidase
-makes B-galactoside
-ferments lactse
-if no more lactose exists, stops making b-galacosidase
What is genotypic variation?
permanent change
-due to mutation
-ex. sicle cell amenia
-rare (random)
Can genotypic variation be directed?
How does a mutation occur?
-natural mistakes occur
-can be induced
-due to x-rays, UV light, chemicals
-can be lethal
Is E.Coli pathogenic when mutated?
What is resistance mutations?
-occurs when all bactgeria but 1 are killed
-single survival reproduces to give resistance to drug
-selects for mutation
-penicillum kills senisitve cells, not resistance cells
What problerms occur over resistance mutations?
-resistant staphylococcus aureus methillin
What is genetic recombination?
-change in characteristsic
-not mutation
-new bacterial DNA
-not "sexual" reproduction
What is transformation?
-has donor and recipient
-donor dies
-cell breaks apart
-recipient picks up pieces of DNA and gains its charactgeristsics
-splices in existing DNA
What is conjugation?
-analagus sexual reproduction, not sex
What does conjugation donor have?
Genome- circular, contains 1 chromosome
F particle of Fertility factgor-plasmid
contains information for its own replication
-has DNA that controls pilus
-has information for chemical :surface component- reduces neg. charge on surface
What does conjugation recipent have?
-missing plasmid (cannot form pilus)
-more neg. than donor
-gets attracted to donor due to opp. charges
What is the end result of conjugation?
-recombinaion (1/100000)
Donor has episome (genetic factor) attached to genome'
-takes 90-120 min, stoped before completion
-recipient reains neg. charged but w/ new egentic information
-as a result, other plasmids exist in bacteria
What is Resistance Tranfer Factor?
R plasmid has RTF and R genes
-RTF= fertility particle-DNA for conjugation
-has R genes-allows for resistance (ex. anttibiotics, cell toxins, heavy metals)
-major factor why gram neg. bacteria are resistant
What does Beta-lactamase do?
breaks down beta-lactam antibiotics
-penicillin- pinicillinase
What gains resistance after conjugation?
What is transduction?
-due to bacteriophage-virus that attacks bacteria
-virus injects DNA
-virus makes amistake and puts bacterial DNA instead of viral DNA
What is lysogenic conversion?
-pheotypic change
-simialar to transductions
-involves bacteriophage-incorportes viral DNA to bacterial genome
-vrial DNA gives characteristsic it normally doesn't have
What does coryne bacterium dyptheriae cause?
-produces toxins that can kill you
-only strains infected with viral DNA can produce toxins
What does clostritum botulinum do?
-priduces botulinum toxin
-only strains infected w/ viral DNA can produce toxins
What does streptococcus pyogenes cause?
-strep throat
-some strains can produce erythrogenic toxin which causes scarlet fever