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189 Cards in this Set
- Front
- Back
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What are the sizes of microscopic life?
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-up to 1mm= 1000um
-up to 1ym=1000 um |
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what is the size of macroscopic organsisms?
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-1mm-200um= macroscopic
-ex. bread mold (sporangia) |
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At waht size do you use a microscope?
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-200um-200nm
-ex. protozoa, algae, most bacteria, RBC |
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At what size do you view with an electron microscope?
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-200um-.5nm are best conditions
-ex. smaller bacteria, viruses |
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What is flagellum microscopic?
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-smaller than 200 nm
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What are the characteristsics of prokaryotic organsisms?
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-no nucleus, mitochondria, chloroplasts
-no membrane bound organelles -has ribosomes -includes archaea and bacteria |
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what afre differences in cell walls of bacteria and archaea?
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-bacteria cell walls have murein
-archae have no murein in cell wall |
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What are characteristsics of bacteria? some examples?
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-have murein
-phospholipid membrane (ester links) -ex. tuberculosis (genus mycobacterium), cholera (vibrio), and bacillary dysentary (shigella) -bacteria came before archae |
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What are characteristsics of archaea?
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-no murein
-have ether links -ex. extreme thermophils (grow at 45 c-110 c) -methanogens -extreme halophils (live at 30% salt) |
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Whata re the characteristsics of eukaryotes?
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-membrane bound organelles
-nucleus, mitochondria, chloroplasts, and ribosomes exists -includes protista, fungi, animalia, and plantae |
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What are the characteristsics of protista?
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-mostly unicellualr
-simple plants (algae) -simple animals (protozoa) -includes malaria, amoebic dysentary, and simple molds (water molds) |
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What are the characteristsics of fungi?
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-mostly multicellular'
-absorptive heterotrophs |
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What are the characteristsics of plants?
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-multicellular
-photosynthetic autotrophs |
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What are characteristics of animalia?
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-multicellular
-ingestive heterotrophs |
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What are autotrophs?
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-make own food/inorganic-->food
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What are heterotrophs?
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-get food from other sources
-ingestive-endocytosis |
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What are the characteristsics of viruses?
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-not considered living
-acellular -instead infectious agents -includes "cold", aids, hepatitis, herpes, and influenza virus |
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What is the cell theory?
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-needs cell membrane, cytoplasm, and nucleus
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What is phycology?
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-study of algae
-drugs from algae |
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What is mycology?
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-study of fungi
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What is protozoology?
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-study of protozoa
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What is virology?
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-study of viruses
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What is bacteriology?
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-study of bacteria
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What is medical microbiology?
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-study of microbes in relation to diseases
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What is parasitlogy?
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-study of protozoa, helminths, worms, and insects that involve in parasitic methods
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What is immunology?
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-study of natural defense of body (antibodies, antigen, allergies, and hypersensitivity)
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What is molecular biology?
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-study of DNA, RNA, etc (sequencing)
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What is microbial ecology?
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-study of things get broken down by microbes (carbon cycle, nitrogen cycle, etc)
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What is microbial physiology?
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-study of metabolism of microbes
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How are decomposers beneficial of microbes? how are they different from parasites?
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-many are absorptive heterotrophs (saprobes or saprophytes)
-live off dead material -parasites don;t decompose, but absorptive (live off of living matter) |
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How are antibiotics a beneficial aspect of microbes?
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-chemical derived from micro organsisms that in small amounts will inhibit or stop the gorwth of another micro organsism
-includes penicillium (can extract penicillin) -treats some streptococci infections -attacks cell walls only and breaks them down |
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How are chemotherapeutic agents a beneficial aspect of microbes?
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-magic bullet
-attacks diseases but not you |
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How are chemicals and drugs a beneficial aspect of microbes?
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-alcohol and acetic acid
-can put human genes in with bacteria genes to produce insulin as a drug source |
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How is food a beenficial aspect of microbes?
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-mushrooms
-cheeses (penecillium mold) -bread (yeast) -beeer adn wine -yogurt |
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How are research tools a benficial aspect of microbes?
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-to study DNA
-bacterial have 1 chromosome |
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What are detrimental aspects of microbes?
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-spoilage (tyhing sget moldy when wet)
-plant diseases -animal diseases |
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What are light microscopes?
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-use electromagnetic radiation called visible light
-controlled by wavelength |
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What is the wavelength of the light?
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-400 to 800 nm (colors of rainbow)
-left end of spectrum includes x-rays and UV light -right end includes micro-waves and infrared -lower the wavelength, the more energy the light has |
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What is a bright field microscope?
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-has objectives of 4X, 10X, 40X, and 100X
-oculars haev objectives -codensor lens below objectives -magnification from 20X-2000X |
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What is the appearance of field and object of bright field microscope? What is it good for?
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-bright, need to contrast by natural color or staining
-good for alage, protozoa, molds, and yeast |
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What are the names of the various objectives of the bright microscope?
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-4X=scanning
-10X= low power -40X= high power -100X= oil immersion |
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What is resolving power?
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-eyes= .2 mm (200 um)
-light microscope=.2um (200nm) -RP=wavelength/2*NA -NA stands for numerical aperature (how light bends as it goes through glass, contrast only duirng oil immersion) -lower the wavelength, lower the RP |
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What is the dark field microscope? What is the appearance of field and object? what is it good for?
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-same as bright microscope but ahs dark-field stop (important part is center)
-pitch black -objects are stars at night -increase contrast to view -good for looking at live microorgansisms -not stained -won;t see aritfacts -can view motility -can view treponema pallidum (syphilus) and mycoplasma |
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What is a Phase contrast microscope? ?
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-same as bright microscope but has annular diaphram and phase-shifting element
-annular diaphragm gives ring of light and bends it (intiiates effect) -phase-shifting element advances (faster/brighter) or retards(slows/darker) light -fucs direct light and not incident light |
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What is the appearance of field and object of phase-contrast microscopes? What si ti good for?
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-similar to bright field but increased contrast
-good for seeing inside cells |
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What is a flourescence microscope?
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-has intense light source
-has eciter filter that filters out anything greater than 400nm -has barrier filter that blocks out anythung less than 500nm -flourescence dye lets you view object (absorbs energy) |
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What sit he appearance of field and object of flourescence microscope? What is it good for?
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-object will shine under flourescence
-used to view mycobacterium' -waxy lipid (auamine O) absorbs dye -used for immunoflourescnce -attach dye to antibody -antibody attaches to organsism -if have disease, object will shine |
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What is the resolution power for immunoflourescence? Eyes?
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-.2 um for all light microscopes
-.2 mm |
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What is a differenctial interferance contrast microscope?
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-uses prisms to split up light
-similar to phase contrast -increase in contrast, 3D, and colored |
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What are electron microscopes?
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-use e-/ not visible light
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What is a transmission electron microscope (TEM)?
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-need e- source
-need condensory magnet -has flourescent screen, objective magnet, projector magnet, and condensor magnet -a specimen scatters the electrons -resolving power is .0005um (.5nm) -can see inside bacteria and viruses |
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What is a scanning electron microscope (SEM)?
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-resolving power= .01um (10nm)
-can see the surface details of a cells |
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What is Bergey-grouped organsism 1st edition? Phylums involved?
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-cell wall characteristsics
-gram stain is positive when purple, negative when pink -includes grancillicates, firmicates, Tenericutes, and mendosacuties |
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what are gracillicates of Bergey-grouped organsism 1st edition? examples?
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-thin/skin (-)
-ex. e.coli, Klebsiella, neissena, spirochetes, chlamydia, and rickettsiae |
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What are firmicutes of Bergey-grouped organsism 1st edition? examples?
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-thick/skin (+)
-staphylococci, streptococci, bacillus, clostridium, mucobacterium, and corynebacterium |
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Whata re tenericutes of Bergey-grouped organsism 1st edition? examples?
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-soft/skin (no cell wall= -)
-mycoplasma |
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What are mendosacuties of Bergey-grouped organsism 1st edition? examples?
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-archea (no murein)
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What is Bergey-grouped organsism 2nd edition? What phylums are included?
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-recognizes 40 phylum
-includes cyanobacteria, actinobacteria, firmicutes, proteobacteria, chlamydia, and spirochetes |
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What are cyanobacteria of Bergey-grouped organsism 2nd edition?
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-blue/green bacteria, photosynthetic (gram -)
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What are actinobacteria Bergey-grouped organsism 2nd edition? Examples?
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-gram +
-high guanine and cytosine ratio -includes mycobacterium and corynebacterium |
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What are firmicutes of Bergey-grouped organsism 2nd edition? Examples?
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-low G+C ratio
-includes staphylococci, streptococcibascillus, clostridium, and mycoplasma |
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What are examples of proteobacteria of Bergey-grouped organsism 2nd edition?
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-e.coli, klebsiella, neisseria, ad ricketlsine
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What is chlamydia of Bergey-grouped organsism 2nd edition?
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-trachomatis
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What are spriochetes of Bergey-grouped organsism 2nd edition?
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-includes syphillus
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What is the shape of cocci? examples?
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-round
-staphylococcus-boils, carbuncles -streptococcus- sore throat, pneumonia -neisseria- gonorrhea, meningitis |
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What is the shape of bacillus? examples?
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-rod shaped
-clostridium- tetanus, botulism -e.coli-diarrhea -klebsiella-pneumonia -cornyebacterium- diptheria |
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What is the shape of spirillum?
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-vibrio (rod or spiral), can cause cholera
-spirochetes-treponema, borrelia, cause syphilis and lyme disease respectivly |
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What is the size of cocci? rods? spriochetes?
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-1 um
-.5 um X 2um -.5 um X 1-14 um |
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What is the glycocalyx? What are the 2 types? chemistry? Regulation?
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-outermost cell layer
-non-living -extracellular -non essential -includes slime layer (looks like shiny covering) and capsules (looks like mucus) -proteins/ polysaccharides -genetics and nutrition |
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What is an exmaple of a slime layer? capsule?
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-staphylococcus
-Klebsieela, pneumonae, streptococcus pyogenes, bacillus anthiacis (anthrax) haemophilus influenzae |
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What are the fucntuons of glycocalyx?
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-capsules stick together in micro colonies providing protection against dehydration and chemicals
-WBC can;t phagocytize b/c of size -streptococcus pyogenes have hyluronic acid -capusles can stick to toehr objects and spread disease -capsules can stick to host (virulent) |
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What are the general properties of the cell wall?
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-nonliving
-not extracellular -integral -dry weight (40%) |
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What are the fucntions of the cell wall?
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-prevents plasmoptysis (bursting)
-inside hypertonic -outside hypotonic -stabilizes cell shape -supports flagella -acts as a sieve (protection) |
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What is the shape of bacteria without a cell wall?
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-cocci
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What is the chenistry of murein in cell walls?
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-made up of peptidoglcan
-NAM (N-acetyl muramic acid) -NAG (N-acetyl glucosamine) -NAG has chitin, unique to bacteria -covalently bonded -has peptide interbridges |
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What are chemicals that break up the cell wall? How?
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-penicillins- prevent peptide interbridges from forming (need growing bacteria)
-cephalosporins- same as penicillins -lysozyme- works on peptide interbridges (but digested) -alcohol- works on outer membrane of cell wall -detergents- works on outer membrane of cell wall |
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In which gram type is most murein located?
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-gram + (50-90%)
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What is the thickness of murein in gram + and -?
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-20-80 nm in pos.
-10 nm in neg |
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In which Gram type is Teichoic acid located?
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-gram positive only
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in whgich gram type is lysine located?
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-gram positive only
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In which gram type is O-polsaccharides located?
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-gram negative only
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In which gram type is Diaminopimellic acid located?
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-gram negative only
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In which gram type is porins located?
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-gram negative only
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In which gram type is there an outer membrane?
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-gram negative only
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What is the difference in periplasmic space b/t gram nega nd positive bacteria?
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-small in grma positive
-large in gram negative |
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What is the outer membrane of gram negative bacteria?
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-lipopolysaccaride
-makes gram negative bacteria more resistant -protects it against antibodes, bile, lysozyme, and heavy metals |
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What is the periplasmic space of bacteria?
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-space in b/t cell membrane and outermembrane in gram neg.
-space in b/t cell membrane and peptidoglycan in gram positive murein layer within it -contains perplasm and enzymes -functional |
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What is a protoplast/
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-lacks cell wall
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What is spheroplast?
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-outer membrane exists
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What are the characteristics of the cell membrane?
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-phospholipoprotein membrane, plasma membrane
-first living part of the cell (protoplast) -differentially permeable (regulates some of what is transferred through in and out of the cell) -uses a fluid mosaic model -selective permeable -contains cholesterol |
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What are phospholipids of the cell membrane?
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-consists of 2 fatty acids, glycerol, phosphate, and a variable organic/alkyl group
-glycerol is a 3 carbon alcohol -fatty acids are long chains of carbon and hydrogen, with the exception of the end carboxyl group -glycerol and fatty acids bind in a condensation reaction/dehydration synthesis -phosphate added at C-3 -amphipathic |
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What is amphipathic about phospolipids?
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-phophate head is hydrophilic
-lipid tail is hydrophobic |
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What is the fluid mosaic model of cell membranes?
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-phosholipids molcules and the protein can move
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What is selectively permeable about the cell membrane?
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-exchange of gases
-membrane proteins=enzymes for respiration -our mitochondria (has DNA and respiration) use to be a bacteria |
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What is cholesterol of cell membranes?
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-found in mycoplasma (which is missing a cell wall)
-found in animals (not in bacteria) -not found in fungi (has ergosterol instead) -a steroid |
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What is a nucleoid of microbes?
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-non nucleus
-bacteria's genome (has 1 circular chromosome condensed in area not surrounded by a membrane |
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What are plasmids?
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-bacteria have additional DNA in this form (extrachromosomal)
-circular in shape but shorter than bacteria genome -generally contain information regarding resistance |
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What are flagella? Example?
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-organelles of locomotion
-arise from the inside of the cytoplasm and are attached to the cell wall -made of 1 filament in bacteria/prokaryotes -more in eukaryotes, 9 outside, 2 in center (uses undulating movement) -provide movement by rotating -only about 10% of bacteria are motile -increases virulence -treponema pallidum (uses flagella to attach to skin cells) |
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What are fimbriae of microbes? Examples?
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-shorter, thinner, and more numerous than flagella
-found in both motile and non-motile bacteria (not used for locomotion) -used for attachment -Nessaria (gonorrhea) -E. Coli attaches to intestinal tract -nonvirulent without it |
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What are pili of microbes?
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-traditionally called "sex" pilus b/t looks liek a cell undergoing conjugation
-form of genetic recombination in which th two halves share DNA |
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What are Endospores of microbes? Examples?
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-fomred on the inside of cells
-most resistance structures in a living microorganism -located in vegetative cell -bacillus -clostridium -sporosarcinae -coxiella byrbati -very resistant to heat and chemicals |
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What is a solid culture medium? Liquid? alive?
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-agar plate
-tube broth, milk -host |
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What is a culture?
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-a mass of organisms
-forms colonies on agar plate -forms cloudy solution in tube broth |
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What is inanimate media?
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-media that is not alive
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What is nonsynthetic media? Examples?
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-complex
-at least one ingredient in the media is not chemically defined -autotrophs- need inorganic media -heterotrophs- need organic media -hypotrophs (obligate parasites)- usually intracelluar and need something alive to live on |
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What is natural media? Examples?
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-media you take from the envrionment
-milk -dead branch -soil |
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How is milk a natural media?
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-inanimate, nonsynthetic, natural media, heterotrophs (contains organic compounds)
-when you make yogurt, you add bacteria to the natural milk media |
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How is a dead branch a natural media?
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-inanimate, non-synthetic, natural media, heterotrophs
-can be used to grow mushrooms |
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How is soil a natural media?
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-inanimate, non-synthetic, natural media, heterotroph/autotroph
-can be used to grow mushrooms or algae |
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What are disadvantages of natural media? Advantages?
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-non chemically defined= non very suitable for strict scientific study
-not sterile -it could be the only media your organisms can grow on 0some organisms are non-culturable -good for commercial applications |
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What are infusional hot water extracts?
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-includes teas and brain heart infusions
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What are brain heart infusions? Advantages? Disadvantages?
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-100 c= cow brains and hearts are boiled
-extracts are taken, evaportated and sold in powdered form -121.5 degrees C to sterilize -can be used for clinical isolates -natural and sterile (pure cultures) -can be made from soil, pond water, to grow cultures on a natural media -some organisms will not grow on it because the chemicals are changed when they are heated up -not chemically defined |
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What is synthetic media? Examples?
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-all chemical components are completely defined
-pure chemicals added to grow specific organisms -amino acids- as a source of nitrogen -sugars added as a source of carbon -ammonium, potassium nitate added as a source of nitrogen for autotrophs -CO2 inorganic source of carbon for autotrophs |
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What are the advantages of synthetic media? Disadvantages?
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-chemically defined and sterile
-pure cultures grown -can be autoclaved -expensive and are therefore not suitable in a clinical setting |
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What is isolation media? Exmaples?
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-goal is to isolate organism from its natural envrionment and grow it on a medium
-complex -to isolate marine organism, harvest sea salt -for human pathogen, use fluids from humans (BHI and blood) -for soil isolate- add soil extract |
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What is differentiation media?
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-react or look different
-used by seeing a difference in the appearance of the media or a difference in the appearance of the culture -helps us differentiate b/t different species -used as a third level of identification, based on enzymes of bacteria |
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What is blood agar plate?
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-differentiation media that tests for hemolysis (breakdown of blood/hemoglobin in blood)
gamma reaction- no hemolysis beta hemolysis- complete breakdown of blood (see clear area) alpha hemolysis- partial breakdown of blood |
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What is mannitol salt agar?
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-differentiation media used for growing out and identifying staphylococcus aureus
mannitol is sugar alcohol only staph aureus can digest -acid produced by fermentation -turns red when staph present |
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What is MacConkey's agar?
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-differentiation media
-has lactose sugar in it -used to detect choliforms (bacteria in intenstines) -breakdown produces acid (colony turns pink) |
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What is eosin methylene blue agar?
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-differentiated media
-has lactose, causes colonies to turn purple |
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What is selective media?
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-ingredients select for/favor the growth of an organism
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How is mannitol salt agar selective media?
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-has 7.5% salt
-favors the growth of staphylococcus aureus and inhibits the growth of many other bacteria |
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How is McConkey's agar selective media?
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-lactose
-contains bile (anionic detergent) -inhibits G+ -allows for G- bacteria (E. coli) |
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How is eosin methylene blue selective media?
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-inhibits Gram +
-allows for G- bacteria -contains lactose and dyes |
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What is enriched media?
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-fastidious- extra ingredients for some organsisms to grow
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How is blood heart infusion enriched media?
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-strep pneumoniae does not grow on plain BHI
-becomes chocolate agar when heated |
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How is lowenstein jensen media enriched?
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-grows mycobacterium using potato starch and eggs in medium
-malachite green inhbitits G+ |
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What kind of medium is blood agar?
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-isolation
-differenctial -enriched |
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What kidn of medium is chocolate agar?
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-isoilation
-enriched |
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What kind of medium is chocolate agar?
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-isolation
-enriched |
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What kinbd of medium is louenstein jensen?
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-isolation
-selective -enriched |
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How do you have liquid consistancy?
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- to make a broth, like brian heart infusion, put in culture tube
-and add water -clear when microorganisms are not present -cloudy when present |
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What is a liquidfiable solid media? How do you make it?
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-example is brain heart infusion agar
-take broth and add 1.5% agar, which makes it a liquefiable solid (red algae have this for low tide) -heat broth with powdered agar up to 100 degrees C, agar becomes soluble and dissolves -then heat to 121.5 degrees to sterilize -cool to 45-50 deg. (called molten agar) -solution solidifies at 40C to become the gel-like consistency we see on plates (cna be streaked) -can any point be reheated to 100 deg to be liquified |
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What is a solid media?
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-once a solid medium is solidified, it cannot be melted
-blood/agar plate is example -once blood is added to agar and solidifed, blood is bright red -heated up to 100 deg to melt, blood turns brown - |
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What is silica based mediums?
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-very good for autotrophs
-contains no organic compounds |
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What is animate media? Examples?
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-alive
-used for growing hypertrophs -cell or tissue culture -embryonated egg |
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What is an obligate parasite?
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-needs animate media
-intracellular -grows on something alive and does damage -includes viruses, chlamydiae, and rickettsiae |
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What is afaculative parasite?
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-animate media not required
-example is streptococcus pyogenes |
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What is a cell or tissue culture? how do you make it?
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medium within a medium
-inoculate liquid medium in cells -cells replicate and multiply through mitosis, small amount added to medium -only viruses that infect the cell can grow |
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What is the cytopathic effect? examples?
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-canb;t see virus, just damage done
-includes giant cells (cell membrans of seveeral cells fuses) (herpes simplex) -includes inclusion bodies such as intranuclear (CMV can cause large cells, hides in nucleus and can cross, includes herpes) -such as intracytoplasmic (like rabies, look for inclusions in brain known as negri bodies) |
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What is the plaquing technique?
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-grow out cell in a monolayer
-add virus, which destroys cells -bare spots or holes are formed by virus -can be used to enumerate virus particles pr ml of vaccine -includes polio virus lyses |
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What are the disadvantages of an embryonated egg as an animate media?
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-difficult to oculate b/c shell is very hard
-not sterlie -difficult to oculate specific parts -chlomidyae, rickettsia, and influenza/flu virus are exaples that can be grown |
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What cna be grown in an intact animal or plant for culturing?
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-hepatitis B- in primate
-syphillis- in rabbits (treponema pallidum) -leprosy- in armadillos,chimps (mycobacterium lepra) |
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How is moisture a requirment of culture media?
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-should contain 75-95% water
-microorg. get nutrients by diffusion -enzymatic hydrolysis occurs- breaking down food with addition of water |
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How is food a requirement of culture media?
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-autotrophs need the correct inorganic nutrients
-heterotrophs need specific organic materials added hypertrophs must have live media at the correct level |
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How is pH a requirement to culture media?
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-most bacteria requir a neutral pH of 7
-an organism can sometimes produce acid or can make the media more alkaline -proteins act as a buffer, amino group can donate or accept a hydrogen depending on what conditions exist -peptone and casin hydrolysat both act as buffers |
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How is sterility a requirement for culture media?
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to be sterlized= at 121.5 deg. celsius for a minimum of 15 min (get pure cultures)
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How are injurious chemicals a requirement for culture media?
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-frequently, undefined media may cintain chemicals that are injurious to the microorganisms you are tyring to grow
agar for instance may contain inpurities you get it, therefore, some people "wash" their agar b/f they use it |
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How is tonicity a requirement for culture media?
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-media need to be hypertonic to the microorganisms so that water flows into the cell (turgid)
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What is growth of microbes?
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-number of individuals, noty size
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What is binary fission?
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-to split into 2
-can occur rapidly -number doubles= esponential growth/logarithmic growth |
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What is the growth curve?
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-predicts the growth of an organism over a time span
-only viable cells, or ones that are alive, are counted |
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What are the 4 distinct phases of the growht curve?
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-lag phase- anytime a population enters a new environment, it undergoes a lag phase b/f it can grow rapidly
-exponential growth phase- rapid growth of the population occurs -stationary phase- flat phase in which population of the organism equilibriates, equal number of orgaisms are born and die, constant, limiting factor is food log death phase- a large number of individuals die |
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How long does the growth curve last for bactereia? Example? Significance?
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-for bacteria, the entire grwoth curve takes about 48 hrs to complete
-with 10mL of liquid culture, after 10 hrs ther are 10 billion cells -growth curve shows us exacly why it takes sucha short period of time to get sick -growth curve is also important b/c they help us predict the numbers of bacteria that may exist at any given time |
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What is cultural enumeration?
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-uses only viable cell counts
-every individual cell capable in a 24 hour period of growing into a separate colony -cells must be spread apart far enough to achive isolation clusters or pairs calleed colony forming units can't be split -the goal in separating bacteria is therefore to get individual cells and CFU's isolated so that they can grow isolated colonies |
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What is the direct cultural method of cultural enumeration?
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-direct refers to the fact that every cell or CFU forms a separate colony so that you can directly count all of the cells
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What is the colony count plating method?
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-in our 10 mL sample, huge amounts of cells that can;t be counted 1 by 1
-take 1mL of it and plac in 9mL of sterile saline, that 1 mL contains 1 billion cells -when this process is repeated 9 times, this is called a serial dilution -take 1 mL from each dilutiona and place on agar plate -25-250 colonies can bee counted, more than 250 is called TNTC or too numerous to count |
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What is the disadvantage of colony count plating method? Advantage?
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-method is slow, need to allow cultures to b incubated
-advantage is it makes counting fairly easy |
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How do you count the number of colonies in colony count plating method?
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-number of colonies times the dilution factor
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What is the membrane filter growth method of cell counting?
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-a membrane filter is used in this method has holes that are small enough to allow liquid to pass through but bacteria to remain behind
-bacteria from filter is placed on agar plate and incubated to form colonies -th density of bacteria must be low to use this -every cell trapped forms one colony |
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What is th indirect cultural method of cell count?
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-indirect is when not ach individual is counted
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What is the most probable number (MPN)? Method?
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-used for testing water for coliforms
-set up 15 tubes -100 mL, 5 tubes with 10mL, 5 with 1mL, and 5 with 1/10 mL each -each tube has another tube to cathcn CO2 -after tincubatd, look to see how many tubes have bubbles, ones with have a high concentration of e.coli -this method ustilizes ranges, which can be gotten by a colony count plating method -doesn't give an exact number |
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What is the adavantage of non-cultural enumeration of cell count? disadvantage?
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-fast
-counts dead ones, as well as artifacts |
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What are th direct method of non-cultural enumeration?
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-cytometer count- has grid for counting
-usd freqently in research -coulter counter- a long tube with an electron beam passing through it is used -counts each particle that passes through and breaks the beam (counts every particle |
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What are the indirect methods non-cultural enumeration?
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-total volume- centrifuge tube is used
-ingredients are mixeed and solids sink to bottom -sampl taken and cntrifuged again -use colony plate count -turbidometric- uses spetromteer -aborption is rlated to conntration of chemicals or cells -more light absorbed, more growth |
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What is variation?
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-any change in charactristics from the parents
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What is phenotypic variations?
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-temporary, common, change in exprssion of a gene
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What is morphological variation?
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-individual cells
-size/shape= temporary -shape of cells change through the growth curve (mature is smaller and young is bigger -shorter in agar and longer in broth |
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What is cultural variation? example?
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-what you see in agar plate
-serratia marcescens (gram neegative rod) -at 37 deg C, colonies are white -at 25 deg C, colonies are bright red |
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What are physiological variations of microbes? Example?
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-has to do with enzymes
-e.coli: B-galactose -genes shut off without lactose (which turns on the genes) -B-galactosidase breaks down B-galactoside (also known as lactose) -if you don't drink any milk, thn only 3 moleecules of nzyme in E.coli -presence of lactose=turns ona gene and produce 3000 enzymes |
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What is a genotypic variation?
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-mutation (change in amino bases/genes
-permanent (genes can't be reverted back) -rare (only small percent of all genes actually works) -random (unpredictable, spontaneous) -mutations occur by natural mistakes -radiation, UV light, and chemcials affect th rate of mutations -most are lethal |
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What is the colony and morphology of smooth form mutated microbes?
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-smooth, round, and chiny (wet)
-singles, normal for e.coli |
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What is the colony and morphology of rough form mutated microbes?
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-wrinkled (chains), irregular, dull
-chains, normal for bacillus subtilis -mutation for e.coli |
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What is the colony and morphology of mucoid form mutated microbes?
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-smooth, round, mucoid (looks bigger)
-appear as singles and capsules -normal for klebsiella pneumoniae |
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What are resistance mutations? Example?
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-causes reistance to drugs/antibidotics
-penicillin is put in plat with staphylococcus -most bacteeria will die except 1/billion -whole colony ends up being resistant |
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What is genetic recombination?
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-not genotypic nor phenotypic
-transfer new bacterial DNA to another bacteria -not sexual reproduction -no zygote or meiosis occurs -just have donor and recipient |
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What is transformation?
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-when bacteria dies, DNA disintergrates and rcipient picks up DNA from donor
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What is conjugation?
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-bacteria conjugate, not sexual reproduction
-both donor and recipient stay alive |
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What is F+ mating type of conjugation?
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-Donor
-contains genome (cirucular and 1 chromosome -F factor is fertility factor (plasmid) -codes for pilus -contians information for its own replication -has DNA that controls pilus -has information for chemical (surfac component that reduced negativ charge on surface) |
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What is the F+ component of conjugation?
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-recipient
-missing plasmid (can;t form pilus) -more negative than donor |
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What is siginifcatn about the differences of charges of the F- and F+ factor?
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-attact each other
-forms pilus -fertility factor in F+ is duplicated and tranferrd to F- -F- becomes F+ b/c of feretility factor -end result rarly has recombination (1/100000) |
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What is high frequency of recombination (HFR)?
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-donor
-1/100 -has episome F-(fretility factor attachd to genome -genome has to break and be transferred across -takes 90-120 minutes to tranfer complete genome -F- remaing F- but now has new genetic info -if not incorporated, dies |
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What is resistance transfer factor or R plasmid?
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-RTF is equivalent to fertility particle (DNA for conjugation)
-codes for resistant for antibiotic, cell toxins, and heavy metal -occurs frequently in G- bacteria -occurs mor often than mutations |
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What is beta-lactamase?
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-breaks down beta-lactam antibiotics
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What is penicillinase?
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-breaks down penicillins
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What is cephalosporinase?
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-breaks down in cephalosporins
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What bacteria usually have penicillinase and cephalosporinase?
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-staph and neisseria
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What is transduction?
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-due to bacteriphage (virus that attacks bacteria
-has its own DNA along with a little piece of the bacteria's DNA -transfer the bactrial DNA into another bacteria by accident |
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What is lysogenic conversion? Examples?
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-not really considered genetic recombination
-phenotypic change -involves bacteriophage (herpes) -corynebacterium dypthriae (produces a toxin that attacks heart and kills) -clostridium botulinum (botulinum toxin) -streptococcus pyogenes (can cause scarlet fever, produces erythrogenic toxin) |
