Brady Test 1 Review – Flashcards
Unlock all answers in this set
Unlock answersHeterotrophs |
Can't Make own food ex. bunnies, people |
Saprophytes |
Eat Dead/ Rotting Organisms ex. fungi/ bacteria |
Nitrogen Cycle (Order) |
Nitrogen Gas Ammonia Nitrite Nitrate Amino Acids/ Proteins |
Bacteria That Fix Nitrogen |
Rhizobium, Azotobacter, Rotospirillium |
Rhizobium |
An important nitrogen fixing bacteria |
Sulfur Cycle (in order) |
Hydrogen Sulfide Sulfur Sulfite Sulfate Amino Acids/ Proteins |
Sulfur-Changing Bacteria Examples |
Thiobacillus, Desulfovibrio, Beggiatoa |
Bacteria that do the sulfur cycle backwards (take amino acids and make Hydrogen Sulfide) |
Proteus vulgaris, Salmonella typhi |
Methods of Organization |
Phenetic Phylogenetic |
Phenetic |
Classification by what they look like Shape, size, morphology |
Phylogenetic |
Classifying with differences such as:
uses genetic material such as tRNA and rRNA Composition of DNA Differences in cell membrane lipid structure Cell wall structure Antibiotic Sensitivity |
The Domains |
Eucarya
Bacteria
Archea |
Domain Eucarya |
have nuclear membranes cell walls if present are made of cabohydrates Not sensitive to antibiotics ribosomes are different |
Bacteria Domain |
Prokaryotic organisms cell walls = peptidoglycan no nuclear membrane sensetive to antiobiotics |
Archaea Domain |
Prokaryotic cell walls not peptidoglycan Extreme environments (halophiles, methanogens, hypothermophiles) not sensitive to antibiotics |
Peptidoglycan |
Its in cell walls of bacteria |
Strain Types |
Biovar
Morphovar
Serovar |
Biovar |
strain with biochemical and physiological differences; diff proteins and enzymes |
Morphovar |
stain with differences in shape and physical
there are strains that have color pigment or lack it |
Serovar |
varient in prokaryotic strains due to antigen differences |
Levels of Organization (starting with Domain) |
Domain Kingdom Phylum Class Order Family Genus - Cap species - lower case |
Methods for Studying microbes |
Inoculation
Incubation
Isolation
Inspection
Identification |
Inoculation |
taking a small sample, putting it on growth media |
Incubation |
growing the sample under best circumstances |
Isolation |
Separating microbes to form pure colonies |
Inspection |
examining colonies and cells |
Identification |
putting them in the right groups so you can name them |
Inoculum |
term for small sample of a microbe |
Medium / Media |
substance which contains nutrients for the growth of the inoculum |
Turbidity |
cloudiness in liquid media |
Fastidius |
Picky |
Fastidius Heterotroph Examples |
Legionella
Bordetella pertussis
Helicobacter pylori |
Parasite |
lives in or on other living things |
Obligate Parasite |
Cannot survive outside a living thing
"Harder to catch" |
Facultative Parasite |
A parasite that can survive outside a host |
Methanogenesis |
process done by certain autotrophs create methane gas |
Autotrophs |
create their own food |
Extreme dehydration (of a microbe) |
the microbe goes down to 20% water
(leaves them dormant) |
Obligate Halophiles |
microbe that must have high salt levels
ex. Halobacterium |
Facultative halophiles |
can tolerate salt levels (Halotolerent) |
Facultative parasite/ halophile example. can stand extreme pH too, also saccrotolerent |
Staph |
Saccrophile |
needs high levels of sugar |
Acidophiles |
need low pH
ex. Helicobacter pylori, Euglena mutabilis |
Alkalinophiles |
Like Higher pH |
Methods of classifying growth media |
Physical types
Origin
Function |
Broth |
liquid medium |
Plate, Slant, Deep |
Solid Media |
Gel |
Semisolid Medium |
Physical Media Types |
Broth Solid Gel Living Media |
Media types based on origin |
natural
synthetic |
Funtional types of media |
Nutrient Enriched Selective Differential |
Plate |
Solid medium in a petri plate |
Slant |
Solid medium in a test tube |
Living media |
used for examining viruses and microbes like syphilis and leprosy ex. chick embryos and experimental animals |
Natural Media / Nonsynthetic |
comes from natural sources, exact composition of the medium is not always known
Blod, tomato, animal extracts, milk agar |
Synthetic Medium / Minimal medium |
Completely man made medium, composition strictly controlled ex. Simmon's Citrate medium only has one sugar in it |
Enriched Media |
Grow fastidius heterotrophs Heat labile - destroyed by heat Blood agar, Thayer-Martin agar, Milk Agar |
Heat Labile Media Type |
Enriched Media |
General Purpose media examples |
Nutrient Agar/ broth Brain Heart Infusion Trypticase Soy Agar |
Peptone |
buffer to maintain a constant pH in general purpose media |
Acts as a buffer in general purpose media |
Peptone |
Selective media |
So microbes will grow, some will not ex. EMB, MSA |
EMB (Eosin Methylene Blue) |
Selective - crystal violet kills gram positives Differential - lactose fermenters (E. coli) |
MSA Manntiol Salt Agar |
Selective - high salt concentrations so Staphylococci and Halophiles can grow Differential - Staph. aureus will cause the medium to change yellow |
Differential media |
provides visible diff between organisms, color |
Phases of Microbial Growth / Disease Path |
Lag Log (Exponential) Plateu Log (Death) |
Generation Time |
Time required for a cell to divide 20min for E. coli |
Factors that affect microbial growth |
Temperature
Oxygen Requirements |
Psychrophiles |
like cold 0-15'C ex. Psychrobacter |
Facultative psychrophile/ psychrotroph |
can grow in refrigeration and have an optimum temperature of 20'C-30'C |
Mesophile |
between 20'C and 40'C pathogens |
Theromophiles |
Grow at above 50'C ex. Thermous aquaticus |
Aerobes |
Need Oxygen for metabolism ex. Micrococcus and Pseudomonas |
Obligate anaerobes |
Cannot tolerate Oxygen ex. Clostridium sporogenes |
Clostridium sporogenes |
Obligate anaerobe |
Examples of Aerobes |
Micrococcus and Pseudomonas |
Facultative anaerobes |
Can tolerate Oxygen ex. E. coli |
Microaerophiles |
Requires small amounts of Oxygen ex. Treponema pallidum (syphillis) |
Treponema pallidum |
Microaerophiles Syphillis |
Capnophiles |
grow best at a higher carbon dioxide tension than normally in the atmosphere |
Axenic |
pure culture |
Isolation methods |
Streak plate Dilution |
Maintaining / Preserving Cultures |
Periodic Transfer Preservation under oil Lyophilization |
Lyophilization |
Freeze dry the microbe |
strepto- |
chain of cocci or bacilli |
sarcina |
cube of 8 cocci |
Staphylo |
Grape like cluster of cocci |
3 Shapes of bacteria |
Coccus Bacillus Spirillium |
Coryne |
club shaped bacilli |
Spirochete |
long, slender spiral |
Vibrio |
bent rod |
Reasons to Negative Stain |
Accurate size of cell May reveal capsule |
Capsule functions |
Protect from: dehydration phagocytosis by WBCs |
Magnesium Ribonucleate |
in Gram + |
Characteristics of Gram + |
Has MgRNA sensitive to crystal violet, no EMB growth sensitive to penicillin can form spores produces exotoxins which leave the cell |
Characteristics of Gram - |
No MgRNA Not sensitive to crystal violet, grows on EMB not senstitive to penicilin non spore formers produce endotoxins which arent released |