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Hazards

  • Liquid nitrogen
  • High boxes/lifting
  • Cold room
  • Confined spaces
  • Chemicals
  • Bacteria/microbes
  • Flammable substances
  • Bunsen burners/gas
  • High voltage (electrophoresis etc)
  • Mice
  • Stirring, moving bottles
  • Compressed gas
  • Radiation (EM and ionising)
  • Sharps

OH and S: Work Cover

  • Hazard management
    • Signs
    • Separate cabinet for flammable things
    • Labels (chemicals, electricity)
    • Careful handling
    • Fume hood
    • Tag and test all equipment
    • Open away from yourself
    • Autoclaving
    • MSDS sheets
    • Aseptic technique (sterile)
    • Biological safety cabinets
      • Positive airflow
      • Filter units up the top
      • Especially important for protection against respiratory diseases
    • Sharps containers
    • Never put needle back into its sheath (then you’ll stick yourself… just put it in the sharps container)
    • Protocols/standards procedures
    • Safety showers
    • Clean with biological agents
    • Exits, fire blankets etc
    • Fire stairs
    • Fire alarm
    • Hazard, then let someone know.

Essential items

  • Lab coats
  • Gloves
  • Enclosed shoes
  • Eye protection

Microorganisms

NB: Blood is sterile (unless septicemia)

  • Bacteria
  • Viruses
  • Fungi (including yeasts)

Agar plate

  • Agar = gelatine agent
  • Nutrients added to it for microbes to grow
  • There are selective agars to choose particular organisms (some are fastidious)
  • NA = nutrient agar
    • Some are more fussy than others (fastidious)
    • Add blood… it has lots of nutrients
    • Blood is better for these fastidious organisms.

Throat swab

  • Streak onto plate using sterilised metal loops
  • Streak around the plate, spread out to get individual colonies to distinguish the different microbes (e.g. normal flora from pathogens)
  • One organism = one colony.
  • Can test antibiotics on single colonies (= single organisms)

Fungus

  • Can survive at lower pH and temperature (unlike bacteria etc. that need warmth)
  • Hyphae with spores
  • Drop pH: kills bacteria and allows yeast and fungi to grow up.

Viruses are symbiotic

  • Can’t culture them on their own
  • Can only grow them inside cells
  • Tissue culture and grow virus in that… very expensive
  • Can only see virus under electron microscope

Light microscope

  • Max 100 times
  • Objectives = {10, 40, 100}
  • Eyepiece = {10}

Other notes

  • Urine, blood, heart, lungs are all sterile (provided you’re not infected)
  • Deep in GI tract, we have anaerobes (O2 is toxic to them)
  • Some bacteria can grow in both anaerobic and aerobic conditions.