Basic Laboratory Techniques Quiz

Sterility and Contamination

• An item is either sterile or not sterile, with no in-between states.
• Only sterile items can be placed on the sterile field.
• Hand washing is still necessary even when wearing gloves.
• Gloves should be replaced immediately if they show signs of tears or damage.
• The working area should be sanitized before and after use to prevent contamination.

Media Types

• Indicator (Differential) Media: used to detect specific organisms, causing a change in the indicator (e.g., Blood agar and MacConkey agar).
• Transport Media: used when a specimen cannot be cultured soon after collection (e.g., Cary-Blair medium, Stuart medium).
• Storage Media: used for storing bacteria for a long period of time (e.g., Egg saline medium, chalk cooked meat broth).

Devices and Equipment

• Autoclave: used to sterilize and disinfect objects at 121°C for 15 minutes, with a cooling down temperature of 50°C.
• Membrane filtration vacuum pump: used for sterilization and filtration processes.
• Refrigerator: used for maintaining and storing stock cultures between subculturing periods and storing media to prevent dehydration.
• Biosafety Cabinets (BSC): used for aseptic techniques and handling of infectious materials.
• Cultivation Chambers: used for growing and culturing microorganisms.