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T/F After growth and division, bacteria are twins?
What type of graph do bacteria demonstrate during growth?
4444444444What are the five phases & definitiosn of the exponential growth chart for bacteria?
- 1) Lag phase: no cell division, increase in biomass due to macromolecules
- 2) Exponential (log) Phase: cell division, produce primary mtabolite and virulence factors
- 3) Late log phase: transition, secondary metabolites produced (antibiotics/pigments)
- 4) Stationary phase: zero growth, no nutrition available
- 5) Decline/Death: exponential death, determined only by CFU test
What two measures are used for measuring baterial growth?
- 1) Optical Density: Measures all cells
- 2) Colony forming unit: measures viable cells
What are the five types of bacterial cultivation media?
What type of Media is MacConkey Agar?
Selective and differential
What are three sources of metabolic energy?
T/F anaerobic respiration = fermentation
F, they are not equal
Common carbon sources for nutrition?
What are three basic Growth factors and their products?
- Amino Acids = proteins
- Pyrimidines and Purines = nucleic acids
- Vitamins = coenzymes
What are the five environmental factors affecting bacterial growth?
- Carbon Dioxide
When it comes to environment, what is the difference b/t obligate & facultative bacteria?
- Obligate: no alternative, narrow range of conditions
- Facultative:alternatives, wide range of conditions
Optimum bacterial growth temperature range?
What are the five temperature range bacteria?
- 1) Psychrophiles
- 2) Psychrotrophs
- 3) Mesophiles
- 4) Thermophiles
- 5) Hyperthermophiles
Obligate psychrophiles and their range
- Cold marine environments
Facultative psychrophiles/psychrotrophs and temp range
- Refrigerated conditions
Thermophiles and Hyperthermophiles and temp range
- Hot springs, geysers, volcanoes, etc...
- Thermophiles: > 50C
- Hyperthermophiles: >80C
For pH, what are the three bacteria categories and which is most common?
- **Neutrophile: pH 7.0
Name three enzymes to counteract ROS?
- Superoxide dismutase
Which bacteria require high CO2?
Three classes of bacteria that utilize water?
- Halophiles: High salt
- Osmophiles: high osmolarity/sugar
- Resistant to dessication
What two bacteria commonly form spores?
What bacteria form cell wall modifications?
Which is more dangerous, BSL-1 or BSL-4?
What is the most important method to reduce transmission of pathogens?
To use an alcohol wash, what should be its concentration?
Three methods of bacterial transmission
- 1) Contact
- 2) Droplet >5micrometers
- 3) Airborne <5micrometers
Name the three decontamination materials?
What is Critical?
contact with sterile tissue or vascular system
What is semi-critical?
contact w/ non-intact skin or mucous membranes
What is non-critical?
no contact with mucous membranes or sterile tissue
What is sterilization?
destroys all microbial life + spores
What is disinfection?
destroys nearly all microbial life
What is decontamination?
reduces microbes to acceptable level
What is cleaning?
remove visible dirt
Name the four microbial control methods?
- Dry heat
- Moist heat
How long should water be boiled to be safe?
how long should medical instruments be sterilized?
What is the common method and temp for pasteurization?
- Method: HTST (high temp, short time)
- Temp: 72C for 15s
What is more effective than dry heat at eliminating spores and denaturing proteins?
What are the three UV Radiations?
UVA, UVB, UVB
Range and example of UVA?
long 400-315 - Blacklight
Range and example of UVB?
medium 315-280 - Vitamin D & sunburns
Range and example of UVC?
Short 280-100 - germicidal (won't penetrate atmosphere)
What rays penetrate packaging?
diff b/t cidal and static?
- cidal: Dead
- Static: not dead but not growing
What are the two tests for chemical agent classification?
- MBC: Minimum bactericidal concentration
- MIC: Minimum inhibitory concentration
What is biocide?
kills living organisms (antimicrobials and pesticides)
What is antimicrobial?
kills or inhibits growth of microorganisms
What is disinfectant?
kills or inhibits growth of microbes on objects or surfaces
What is antiseptic?
kills or inhibits growth of microbes on living tissue (mouthwash)
What is Antibiotic?
Kills or inhibits bacteria
Name the three levels of disinfectants?
What is high-level disinfectant?
kills all microorganisms except spores
What is intermediate disinfectant?
kills mycobacteria, veg. bacteria, viruses and fungi but not spores
What is low level disinfectant?
Kills veg. bacteria, some viruses and fungi, but not spores
Six common topic/oral antiseptics?
- Hydrogen peroxide
- Heavy metal compounds
- Phenol compounds
- Quaternary ammonium compounds
When is an alcohol cleaner ineffective?
When in presence of organic material (should clean debris off first)
When is alcohol more affective?
When diluted w/ water
What three chemicals can't be autoclaved?
- Ethylene oxide