Flashcards
micro exam 3
Cards in this deck (169)
- 1what is taxonomy?the science of classifying organisms
- 2what does taxonomy provide?universal names for organism and reference for identifying organisms
- 3who created a formal system of taxonomy?carl von linne
- 4what are the 3 parts of carls formal system?- classification
- identification
- nonmenclature - 5what is classification?placing organisms in groups of related species, lists of characteristics of known organisms and based on their relatedness
- 6what is identification?matching characteristics of an unknown organism to lists of known organisms. ex. finding unknowns in labs and examining the bacterial traits
- 7what is nomenclature?naming each organism
- 8in classification, what are the 3 domains?- bacteria- normal bacteria
- archaea- abnormal/unusual bacteria
-eukarya - 9what are characteristics of archaea?- different cell walls
-different or modified enzymes
-specialized structures
- have all of these bc they live in extreme conditions - 10what are eukarya?-protists
-fungi
-plants
-animals - 11what is the taxonomic hierarchy? (largest to smallest)- domain (most diverse- largest group)
- kingdom
- phylum (we use division instead)
- class
- order
-family
- genus
- species (most specific-smallest group) - 12how can you expand this classification to make it more complex?adding subclasses or superfamilies
- 13who established the system of scientific nomenclature?linnaeus
- 14each organism has two names called what?- genus (capitalized)
- species (lowercase) - 15what do yo do in bacterial classification?- numerous identification tests
- determine which group or taxa that bacteria belongs to
- known= find group
- unknown = you name it - 16what are the microscopic traits of morphology?- look at cell no colony
- shape of cell (rod or cocci)
- size
- motiliy/presence of flagella
- arrangment
- acid-fast or not (is mycolic acid in cell wall?)
- gram positive or negative - 17what are the macroscopic traits of morphology?- appearance of colonies
- most likely agar or broth
- in agar; elevation, color, texture, size, color
- in broth; aerobic, anerobic, sediment/pellicle/unifrom tubidity
- if blood agar; hemolysis (not many are alpha) - 18what are ecological characteristics of microorgs?- based on their relationship w/ environment
- different growth requirements - 19microorgs markedly differ from what?- different parts of your body
- freshwater
- terrestrial
- marine env - 20what are fairly reliable properties and stable expressions of chemical identities of each species?- enzymes
- biochemcial properties - 21what are examples of biochemical properties?- oxidase test
- catalase test
- DNase media (DNA hydrolysis)
- sugar fermentation (carbohydrate)
- gas production
-H2S production - 22for the TSIA how do you classify it? (a/b/c/d)- gas production
- H2S
- slant reaction
- butt reaction - 23what is a dichotomus key?flow chart using +/- to identify an organism
- 24what are chemical analysis?analyzing the types of specific structural substances that the microorg contains
- 25how do you analyze the types of specific structural substances that the microorg contains?look at the cell wall stucture
- bacteria have peptidoglycan, D- amino acids, peptide crosslinks b/w nag and nam etc - 26what are serological analysis?all bacteria cells have surface molecules that stimulate the immune system which produce protective proteins called antibodies
- 27why can you use antibodies as a means of identifying bacteria in specimens and cultures?the response is so specific and that specifically bind to molecules that induced them
- 28what does phage typing use?bacteriophages that only react with mbs of species. usually a specific receptor on the host cell
- 29phage typing makes a confluent later of what on agar plates?test bacteria
- 30how do you do phage typing?you draw a grid on the bottom of the plate and make a template of the squares, put drops of known phages (one per square) and incubate for 24-48 hrs. look for plaques in the bacterial lawn
- 31in phage typing, what helps determine bacteria relatedness?observation of which phages lysed the bacteria
- 32can microbial genomes be compared directly?yes
- 33are taxonomic similarity estimated in many ways?yes
- 34what is one of the simplest ways to make a genetic and molecular analysis?(ie compare DNA)determine the DNA base composition
- 35what are the two purines of DNA?adenine and guanine
- 36what are the two pyrimidines of DNA?cytosine and thymine
- 37for dsDNA what pairs with T?A
- 38for dsDNA what pairs with C?G
- 39the G+C: A+T ratio is used as?an indicator of relatedness
- 40in prokaryotes, the G+C% ranges from?25-85%
- 41is % within a species constant?yes
- 42G+C involves _ hydrogen bonds3
- 43A+T involves _ hydrogen bonds2
- 44what is needed to break the G/C bonds?more heat than A/T
- 45at what temps do DNA strands separate?90-95 C
- 46what does slowly cooling the DNA allow?complementary nucleotides to hydrogen bond and the DNA hydroizes (reanneals) to form dsDNA
- 47for each organism what is unique concerning DNA?the exact order and arrangement of DNA
- 48what is hybridization?it identifies a bacterial species by analyzing segments of its DNA
- 49what does hybridization require?ssDNA probes to specific sequences of DNA from a particular microbe
ex. ssDNA from E. Coli - 50how is the probe labeled?radioactivity
- 51what is the first part of hybridization?test DNA (weak bacteria) and control DNA (E. coli) are spotted on a filter
- 52what is the second part of hybridization?binding of radioactivity labeled probes to test and control DNA indicated close coreespondance
- 53what is the third part of hybridization?after radioactive probes are allowed to hybridize to the DNA, the membrane filter is washed to remove any nonhybridized prob
- 54why do we asses the amt of radioactivity?the determine relatedness
- 55why is the amount of radioactivity bond important?it helps determine the relatedness of the organism and the same of amt of radioactivity = the same organism (100%)
- 56how is the degree of similarity or homology expressed?percent of radiolabeled test DNA as compared to radioactivity of control DNA
- 57what is the hybridization test used for?diagnosing cause of infection and identifying unknown bacterium or virus
- 58overview of hybridization test- commercially available diagnostic kits
- isolated, denatured, placed on filter and combined with microbe-specific probe - 59in DNA fingerprinting, how do you recognize specific sequences of DNA and break bond b/w adjacent nucleotides?restriction enzymes/restriction endonucleases
- 60what can the enzymes be used for?to cleave DNA at desired sites
- 61what can the restriction fragments be used for?used in the lab to cut DNA into smaller pieces
- 62how do you compare the results of DNA fingerprinting?you run fragments on a gel to compare results; look at the DNA fragments or restriction fragments pattern in the gel
- 63what do gel electrophoresis do?they separate DNA fragments based on mw/size
- 64the DNA samples are placed on what?soft agar gel and subjected to an electric current
- 65a negative charge of DNA molecules causes what?DNA to move toward the positive pole
- 66larger fragments move slower or faster? (depends on size)slower
- 67gel electrophoresis are useful in comparing...genetic similarities
- 68DNA by hybridization & fingerprinting gives info, but the most detailed info comes from?determining the actual order and types of nucleotide bases that code the DNA
- 69how does this work?the sample DNA (ss) -> cDNA -> determines the nucleotide sequence -> computer breaks data bank of known bacterial sequences
- 70in ribotyping, what are used for bacterial identificaiton?nucleotide sequence from 30S ribosome
- 71what happens to the rRNA?it is amplified by PCR and is sequenced
- 72how is the resulting sequence compared?international biotechnology database
- 73what do you do after testing DNA?identify bacteria and place on taxonomic scheme
- 74what provides identification schemes for identifying bacteria and archaea and uses phenotyping?Bergerys Manual of Determinative Bacteriology
- 75what provides phylogenetic info on bacteria and archaea based on DNA?Bergeys manual of systematic bacteriology
- 76are new techniques and bacterias still be discovered?yes
- 77what are the 4 divisions of bergeys manual that bacteria are placed in? (mostly cell wall composition)- division gracilicutes = gram - bact
- division firmicutes= gram + bact
- divison mednosicutes= archae -> unusual cw (mendo)
- division tenericutes= mycoplasms -> lact cw - 78what is a microbial cell composed of?- 70 % water
- proteins
- 96% composed of 10 elements - 79what are the 10 macro elements in a microbial cell?- carbon
- hydrogen
- oxgen
-phosphorous
- sulfur
- nitrgoen
-potassium
-calcium
-magnesium
-ron - 80macro elements are required in large or small amounts in microorgs?large
- 81the first 6 (COHNSP) are components of what?carbohydrates, lipids, proteins, nucleic acids
- 82these components are needed in what quantities?gram quantities
- 83the remaining 4 (K, Ca, Mg, Fe) exist as what?cations (+ charged) and play a variety of roles
- 84these 4 are needed in what quantities?mg quantites (1mg=.001 g)
- 85why is potassium important?essential to protein synthesis and membrane function
- 86why is calcium important?for cell wall and endospore stabilizer
- 87why is magnesium important?membrane and ribosome stabilizer
- 88why is iron important?input for ETC for energy
- 89what are the trace elements needed?manganese, zinc, cobalt, molybdenum, nickel, and copper
- 90what quantities are trace elements needed in?ug (1ug= .000001 g)
- 91what are the importance of trace elements?- normally a part of enzymes and cofactors
- aid in catalysis of reactions
- aid in maintenance of protein structure - 92trace elements such minute quantities are needed from?obtained from air water env in the lab of glassware
- 93enzymes determine what for an organism?the number of nutrients it must obtain to live
- 94why do enzymes determine this?they drive metabolic reactions;if an enzyme is missing and organism is incapable of using a metabolic reaction to produce a certain substance
- 95if an enzyme is missing they take/obtain it from?the environment
- 96how many compounds does E. Coli contain?> 5000
- 97how many compounds does E. Coli need to synthesize this great diversity?only a few such as glucose, trace elements, H2O, and 6 others
- 98bc E. Coli has so many different compounds, what does this say about the number of enzymes E. coli has?it doesnt have to take much from env bc it can make most. it has a high # of enzymes
- 99carbohydrates satisfy what essential nutrients?carbon, hydrogen and oxygen
- 100what is required for the backbone of all organic molecules?carbon
- 101molecules serving as carbon sources usually also contribute both?hydrogen and oxygen
- 102what are inorganic nutrients?molecules that contain a combination of atoms other than carbon and hydrogen
- 103what are examples of inorganic nutrients?metals and their salts
- magnesium sulfate
- ferric nitrate
- sodium phosphate
- gasses
- oxygen
-CO2
- water - 104what are organic nutrients?contain carbon and hydrogen atoms and are usually the products of living things
- 105what are examples of organic nutrients?- methane (CH4) (smallest)
-carbohydrates
-lipids
- proteins
- nucleic acids - 106nutritional types are based off..?carbon sources
- 107what in an autotroph?an organism that uses CO2, an inorganic gas, as its carbon source
- 108are autotrophs nutritionally dependent on other living things?no
- 109are autotrophs parasites?no; they convert CO2 into various organic compounds for its use
- 110what is the problem for autotrophs?it is very expensive energy wise to use CO2 as a carbon source
- 111what are special about autotrophs?they are often the basis for food
- 112what is a heterotroph?an organism that must obtain carbon in an organic form made by other living organisms such as proteins, carbohydrates, lipids and nucleic acids
- 113overall are heterotrophs flexible in regards to carbon sources?yes
- 114is there a naturally occurring organic compound that cant be broken down by some microbe?no
- 115do microbes use the same organic compounds?no, different microbes use different organic compounds
- 116what are actinomycetes?filamentors bacteria in soil such as rubber, parafin, ehtanols
ex. pseudomonas anarosa
- over 100 organic compounds - 117what are the main determinants of nutritional types?1- carbon source (hetero/auto)
2- energy source (photo/chemo) - 118what is a phototroph?gains energy through photosynthesis and often serves as basis of food chains
- 119what is a chemotroph?gains energy from oxidation of chemical compounds so it loses H+/e-
- 120what is a chemolithotroph?"rock eaters" they oxidize inorganic compounds
- 121what is a chemoorganotroph?they oxidize organic compounds for energy
- 122how do environmental factors influence microbes?they aid in the control of microbial growth bc microbes are exposed to a wide variety of env factors. they also help you understand the ecological niches of microbes
- 123environmental factors fundamentally affect the function of ?metabolic enzymes
- 124what are these env factors?- temperature, pH , gas req such as oxygen, osmotic pressure, radiation, barometric pressure, and ecological associtations
- 125in order for microbes to survive..they must be able to adapt
- 126what are the 3 cardinal temperatures?minimum temp=lowest temp that permits a microbes growth/metb
maximum temp= highest temp that permites...
optimum temp= promotes the fastest rate of growth and metb - 127are cardinal temps fixed?no bc environmental factors influence it
- 128what are psychrophiles?cold loving; -10C to 25C
opt is 10-20C
can grow in fridge - 129what are mesophiles?10C to 45C
opt is 20-40C
human body is 37C - 130what are thermophiles?30-80C
opt is >45C
Heat loving
composite piles and hot H2O water - 131what are extreme thermophiles?80C and greater
hot springs
deep ocean
no optimum
100C is boiling - 132what is pH?a measure of the hydrogen activity of a solution
- 133what does pH define?the acidity or alkalinity of a solution
- 134what is the pH of pure water?7
- 135does each species have a definite pH growth range?yes
- 136what is the optimum pH range for most orgs and why?pH 6-8 bc acid and case can be damaging to enzymes, CM and other parts of the cell
- 137T/F each species has a pH AND temp growth range?true
- 138what are the effects of pH?related to the concentration of acid in the medium and to the protection that bacterial cell walls sometimes provide
- 139what can changes in pH lead to?denaturing enzymes (proteins) and other proteins and can interfere with pumping ions at the cell membrane
- 140how do many bacteria produce sufficient quantities of acids?as they grow and metabolize in a closed system which can lead to a toxic env
- 141what are acidophiles?they grow at extreme acid pH 0-5.5
- 142what are neutrophiles?they grow b/w pH OF 5.5-8
- 143what are alkalophiles?grow b/w pH of 8.5-11
- 144what is helicobacter pylori?rod/flagella found in the stomach that causes peptic ulcers an dis NOT acid tolerant
- 145how does heliobacter pylori protect itself?grows in protective mucus layers of the stomach and breaks down the urea into ammonia that has a pH 12 so it neutralizes the microenv
- 146what is an important respiratory gas that is highly reactive?oxygen
- 147what toxic products do utilized oxygen transform into?singlet oxygen O2
superoxide ion O2-
peroxide H2O2
hydroxyl radicals OH- - 148what netraulizes these chemicals?enzymes developed by most cells
- 149what enzymes neutralized superoxide ion?superoxide dismutase catalse
- 150what happens when a microbe is not capable of dealing with toxic oxygen?it is forced to live in oxygen free habitats
- 151what is a aerobe?utilizes oxygen and can detoxify it; has a protective enzyme
- 152what is an obligate aerobe?cannot grow without oxygen
- 153what is a facultative anaerobe?utilizes oxygen but can also grow in its absence; prefers O2 but can grow without it
- 154is a facultative anaerobe grouped as a anaerobe?no its grouped as a aerobe
- 155what is a microaerophilic?requires only a small amount of oxygen; grows best at 5% oxygen (atmospheric is about 20% oxy)
- 156with O2 an aerobic respiration..= more energy
- 157what is an anaerobe?doesnt utilize oxygen
- 158what is an obligate anaerobe?lacks the enzyme to detoxify oxygen so cant survive in an oxygen env
- 159what is an aerotolerant anaerobe?tolerates and grows in the presence of O2 but doesnt use O2 (ignores it )
- 160what is a hyperbaric oxygen chamber?O2 pressurized (increases oxygen) used for ppl who have anerobic gas gangrene infections
- 161what does the availibility of water in an env vary and depend on?the actual amt of water and on the solute concentration i water
- 162most microbes exist under what conditions?hypotonic and isotonic
- 163what are halophiles?require a high concentration of salt
- 164what are osmotolerants?dont require a high concentration of solute but can tolerate it when it occurs
- 165what is isotonic?no movement/concentration gradient
- 166what is hypotonic?H2O flow into cell; cell wall protects
- 167what is water activity?a measure of the water that is available for use by an organizm
- 168how is AW lowered?by adding solutes to a solutions thus the increased solute concentration of the solution and thus the increased osmotic pressure decreases aw
- 169what are solutes?sugars and salts
Information
- Description
- Flashcards on micro exam 3, created by Harley Miles on 04/11/2014.
- Created by
- Harley Miles
- Views
- 11
- Rating