| 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
cna,mac,
*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
genus(capitalized)
species (lowercase)
*Staph. aureus |
| Sterilization:
physical method
chemical method | all microbial life are killed
physical:incineration, moist/dry heat, filtration, ionizing radiation.
chemical: ethylene oxide, formaldehyde, glutaraldehyde, peracetic acid. |
| Disenfection:
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 |
| TYPES OF FIRE EXTiNGUISHERS
A | 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
Alarm
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
disposal
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 |
