MICR 290 FINAL EXAM LATEST 2025 WITH CORRECT
QUESTIONS AND DETAILED ANSWERS/ALREADY
GRADED A+
Risk group 2 - CORRECT ANSWER-Individual risk: moderate
Community risk: low
Risk group 3 - CORRECT ANSWER-Individual risk: high
Community risk: low
Risk group 4 - CORRECT ANSWER-Individual risk: high
Community risk: high
Biohazards - CORRECT ANSWER-Biological materials that can represent a health
hazard to humans, animals, or plants.
Include a wide range of potentially infectious agents, such as bacteria, viruses,
fungi, parasites, & prions.
Risk group 1 - CORRECT ANSWER-Individual risk: low
Community risk: low
,Conditions that research labs are required to operate under - CORRECT
ANSWER-Containment levels (CLs) or Biosafety levels (BSLs) → numbered
according to the biohazard risk group that can be studied in that lab
CL of Queen's laboratories - CORRECT ANSWER-CL1 & CL2
How many CL4 labs in Canada, and where? - CORRECT ANSWER-1, at the
National Microbiology Laboratories in Winnipeg
Safe handling & disposal of biohazards - CORRECT ANSWER-Personal Protective
Equipment (PPE)
Lab coats are absolutely required, (even with Risk Group 1 biohazards). Lab
goggles are also recommended, particularly while carrying out experiments that
can generate aerosols.
Sterilization & Disposal
Lab materials that have been in contact with bacteria (ex: tubes, pipette tips, etc)
should be sterilized, using bleach or an autoclave. Once biohazardous waste is
decontaminated, it can be disposed of with regular non-contaminated lab waste.
The surface of the lab bench must be sterilized using 10% bleach or 70% ethanol.
Lab-based research also requires WHMIS training.
Aseptic technique - CORRECT ANSWER-Strategies and approaches designed to
create a sterile environment, limiting potential contamination by microorganisms
,Pipettes - CORRECT ANSWER-Used to transfer volumes ranging from 1mL -
0.1μL
Advantages of pipettes - CORRECT ANSWER-- Contaminated pipette tips can be
easily disposed of in waste that is to be autoclaved (a measuring cylinder would
have to be sterilized)
- More accurate than cylinders for transferring small volumes
- Cheaper and easier to decontaminate than syringes
How to use pipettes - CORRECT ANSWER-Step 1: Preparation
To transfer a solution, the plunger at the top of the pipette is first depressed,
which lowers the piston. In this step, the plunger is depressed to the first stop.
Step 2: Aspiration
The affixed pipette tip is placed in the solution, and the plunger is released,
raising the piston. This creates a vacuum, drawing the solution into the pipette
tip.
Step 3: Dispense & Purge
Then, the solution is transferred into a different container by depressing the
plunger, which lowers the piston, and ejects the solution. The plunger is
depressed to the second stop, ensuring that all of the solution is expelled from
the pipette tip.
, Step 4: Home
The pipette tip is removed from the solution, and the plunger is released,
returning it to the rest position.
Aspects of aseptic technique - CORRECT ANSWER-Lab surfaces are wiped down
with 10% bleach or 70% ethanol before AND after experiments.
Pipette tips, lab solutions, and media for growing bacteria are autoclaved.
Autoclaves use high pressure steam to kill bacteria. Other lab tools are wiped
down with bleach or ethanol.
Sterile containers (ex: boxes containing pipette tips, Petri dishes) are kept closed
to external air as much as possible.
A Bunsen burner can be used to sterilize common microbiological tools
(inoculation loops, forceps) and the openings of sterile bottles and containers.
They also generate airflow on the bench surface, to draw airborne contaminants
away from research samples and equipment.
For research involving biohazards in Risk Groups 2+, experiments are carried out
in biosafety cabinets. The air inside biosafety cabinets is passed through a High-
Efficiency Particulate Air (HEPA) filter, removing microorganisms. The exhaust air
is usually also filtered, preventing the spread of biohazards into the environment.
Bacterial cell division - CORRECT ANSWER-Binary fission: a process in which one
bacterial cell divides into two identical cells
QUESTIONS AND DETAILED ANSWERS/ALREADY
GRADED A+
Risk group 2 - CORRECT ANSWER-Individual risk: moderate
Community risk: low
Risk group 3 - CORRECT ANSWER-Individual risk: high
Community risk: low
Risk group 4 - CORRECT ANSWER-Individual risk: high
Community risk: high
Biohazards - CORRECT ANSWER-Biological materials that can represent a health
hazard to humans, animals, or plants.
Include a wide range of potentially infectious agents, such as bacteria, viruses,
fungi, parasites, & prions.
Risk group 1 - CORRECT ANSWER-Individual risk: low
Community risk: low
,Conditions that research labs are required to operate under - CORRECT
ANSWER-Containment levels (CLs) or Biosafety levels (BSLs) → numbered
according to the biohazard risk group that can be studied in that lab
CL of Queen's laboratories - CORRECT ANSWER-CL1 & CL2
How many CL4 labs in Canada, and where? - CORRECT ANSWER-1, at the
National Microbiology Laboratories in Winnipeg
Safe handling & disposal of biohazards - CORRECT ANSWER-Personal Protective
Equipment (PPE)
Lab coats are absolutely required, (even with Risk Group 1 biohazards). Lab
goggles are also recommended, particularly while carrying out experiments that
can generate aerosols.
Sterilization & Disposal
Lab materials that have been in contact with bacteria (ex: tubes, pipette tips, etc)
should be sterilized, using bleach or an autoclave. Once biohazardous waste is
decontaminated, it can be disposed of with regular non-contaminated lab waste.
The surface of the lab bench must be sterilized using 10% bleach or 70% ethanol.
Lab-based research also requires WHMIS training.
Aseptic technique - CORRECT ANSWER-Strategies and approaches designed to
create a sterile environment, limiting potential contamination by microorganisms
,Pipettes - CORRECT ANSWER-Used to transfer volumes ranging from 1mL -
0.1μL
Advantages of pipettes - CORRECT ANSWER-- Contaminated pipette tips can be
easily disposed of in waste that is to be autoclaved (a measuring cylinder would
have to be sterilized)
- More accurate than cylinders for transferring small volumes
- Cheaper and easier to decontaminate than syringes
How to use pipettes - CORRECT ANSWER-Step 1: Preparation
To transfer a solution, the plunger at the top of the pipette is first depressed,
which lowers the piston. In this step, the plunger is depressed to the first stop.
Step 2: Aspiration
The affixed pipette tip is placed in the solution, and the plunger is released,
raising the piston. This creates a vacuum, drawing the solution into the pipette
tip.
Step 3: Dispense & Purge
Then, the solution is transferred into a different container by depressing the
plunger, which lowers the piston, and ejects the solution. The plunger is
depressed to the second stop, ensuring that all of the solution is expelled from
the pipette tip.
, Step 4: Home
The pipette tip is removed from the solution, and the plunger is released,
returning it to the rest position.
Aspects of aseptic technique - CORRECT ANSWER-Lab surfaces are wiped down
with 10% bleach or 70% ethanol before AND after experiments.
Pipette tips, lab solutions, and media for growing bacteria are autoclaved.
Autoclaves use high pressure steam to kill bacteria. Other lab tools are wiped
down with bleach or ethanol.
Sterile containers (ex: boxes containing pipette tips, Petri dishes) are kept closed
to external air as much as possible.
A Bunsen burner can be used to sterilize common microbiological tools
(inoculation loops, forceps) and the openings of sterile bottles and containers.
They also generate airflow on the bench surface, to draw airborne contaminants
away from research samples and equipment.
For research involving biohazards in Risk Groups 2+, experiments are carried out
in biosafety cabinets. The air inside biosafety cabinets is passed through a High-
Efficiency Particulate Air (HEPA) filter, removing microorganisms. The exhaust air
is usually also filtered, preventing the spread of biohazards into the environment.
Bacterial cell division - CORRECT ANSWER-Binary fission: a process in which one
bacterial cell divides into two identical cells
