Question Answer
1) Define microbiology a) The study of microorganisms
a) Nutritive growth of wide range of microorg. (most non fastidous) without giving any particular org a growth advantage
*Sheep Blood
b) Differential contains some factors that allow colonies of one bacteria to show some metabolic/culture characteristics that can be used to distinguish them from other bacteria on the same plate
*blood,emb, mac
selective growth of one group of microorg, but not another
*Mac, cna
Supplemental/enrichment lim, chocolatte
When can a specimen be rejected label and requisition dont match, improper transport medium, qns, leaking, transport time longer than 2hrs, dry.
Define genus genus: diff species that have similar morphology, physiology and genetic traits but maintain individual status
strain subset of bacterial special that differ by minor differences
species collection of bacterial strains that share many common physiologic and genetic features
explain nomenclature binomial system
species (lowercase)
*Staph. aureus
physical method
chemical method
all microbial life are killed
physical:incineration, moist/dry heat, filtration, ionizing radiation.
chemical: ethylene oxide, formaldehyde, glutaraldehyde, peracetic acid.
physical method
chemical method
most orgs, not all are destroyed
boiling, pasteurizing, uv light
alcohols, aldehydes, halogens, heavy metals, amonium, phenolics
Material safety data sheets info about the chemical
A-green triangle(trash, wood, paper)
-employs water/all purpose dry chemical

B fire extenguisher red square (chemical fire)
employs foam, dry chemical or co2
C fire extenguisher blue circle (electrical fire)
employs nonconducting extinguishing agents co2 or dry chemical.
RACE acronym Rescue injured
Contain fire
Extinguish fire
discuss electrical safety check cords for fraying, all cords must be 3 pronged grounded, no extension cords
Biocide: (chemical sterilant)-chemical agent that destroys all life
antiseptic: inhibiting the growth of microorganisms w/o killing them
List components of the exposure control plan Provisions
engineering controls
3 mechanisms of genetic change mutation, recombination, gene exchange
Mutation: change in original sequence of a gene
Recombination donor DNA–> recipient DNA
exchange of dna occurs
gene exchange transformation, transduction, conjugation.
Binary fission bacterial replication by cell division
results in 2 daughter cells (asexual process)
Identical DNA
Gram + cell wall composition thick peptido glycan layer, lipoteichoic acid and teichoic acid… some have mycolic acid to fortify the murein layer
Gram – cell wall composition thin peptidoglycal layer, outer layer has lipids, proteins and polysachharides
acid-fast thick peptidoglycan and mycolic acid
Outer Membrane protects cell from external environment
cell wall gives shape and strength to withstand changes in osmotic pressure. prevents cell lysis,protects from mechanical disruption
periplasm only in gram -, helps in detoxification, absorption of nutrients, enzymatic degradation of macromolecules
cytoplasmic membrane regulate transport across the membrane and osmotic barrier, location of electron transport
capsule protect cell from desiccation and toxic materials promotes conc. of nutrients at cell surface. antigenic, illicit immune response
pilli used for attachment, bacterial conjugation, transfer of genetic material in gram – cells.
flagella movement
endospores protect from environment, guarantees survival
endotoxins gram – bacteria produce this
composed of lps
heat stable
low toxicity
exotoxins gram +
composed of protein
heat labile
signs of disease aches, headache, swollen lymph nodes, rashes, redness, cough/sneeze, congestion, nausea/vomitting, diarrhea
prevention of disease immunization and epidemiology
reservoirs human, animal, food, environmental
vectors mode of transmission (direct/indirect)
transient flora don't multiply, shed with host cells
resident flora multiply permanent on the host
pathogen microorg. that cause infection or disease
opportunistic pathogen organism that only cause infection when one or more of the host's defense mechanisms are disrupted
virulence degree of pathology caused by the organism. correlated with ability to multiply in the host
heat fix/methanol fix preserve and fix in position the internal/external structure of organism
crystal violet primary stain binds to bacterial cell walls with – charge
grams iodine increases the interaction between cells and dye so that its more strongly stained
decolorizer acetone/alcohol. damages bacterial with thin cell wall
safranin counter stain. stains all unstained elements
cultivation growing of living materials
in vivo living body of plant/animal
in vitro outside living body/in artificial environment
fastidious have complex nutritional requirements
non fastidious have simple nutritional needs
environmental requirements for the cultivation of bacteria o2 and co2 availability
microaerophillic need low levels of o2
capnophillic grow well with higher co2
faculative anaerobic grow with or without o2
how to evaluate bacterial colony morphologies types of media supporting growth, quantities of each colony type, size, color, shape, surface, odor, gram stain
genotypic criteria identification based on some portion of the genome using molecular techniques for DNA or RNA analysis
phenotypic criteria identification based on observable physical or metabolic characteristics of bacteria. Analysis of gene products, not the genes themselves.
phenotypic criteria used for bacterial identification macroscopic colony morphology (size, shape, color etc)
microscopic morphology (gram stain, wet prep)
environmental requirements for growth, atmospheric requirements, nutritional requirements, resistance to microbial agents.
quality control control of labs analytical error by monitoring analytical performance with known controls and maintaining errors within established limits around the mean control values
quality assurance institutional program designed to assess the success of the total organization achieving its goals
total quality management improve patient care by monitoring laboratory work to detect and correct deficiencies
continuous quality improvement/performance improvement improve patient care by not making a mistakes
2) Describe the basic elements of a quality control program a) Specimen collection and transport
b) Sop’s
c) Personnel
d) Referenc labs
e) Patient reports
f) Proficiency testing
g) Performance checks
h) Maintain qc records
i) Maintain qc stocks
electron microscopy condenser doesn't allow light to hit specimen. Spirochete detection
Fluorescent Microscopy absorb and emit different wavelength of light.
color against dark background
phase contrast microscopy light beams pass through specimen and are partially deflected due to density differences. No stains needed
brightfield light passes directly through specimen and then through lenses that reflect light
specimen collection no transient flora, collected during acute phase of illness, and not prior to ab therapy.
specimen transport within 30min of collection, in biohazard bag, at right temp.
direct microscopic evaluation gram stain, quality of sputum specimens, presences of WBCS

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