Chapter 2 Flashcards
Graduated cylinders capacity range
From 5 mL to 5 L.
Larger graduated cylinders accuracy
Less accurate due to larger meniscus sensitivity to atmospheric pressure changes.
Volumetric flasks accuracy
Within 0.04% of the target volume.
Graduated cylinders accuracy
Within 1% of the target volume.
Common volumetric flasks capacity range
From 10 mL to 2 L.
Equipment for measuring 1 to 25 mL
Vacuum-assisted pipets.
Micropipets accuracy
Varies from 0.5-4% depending on size and volume.
10 mL disposable serological pipet accuracy
Measures to within 0.15 mL.
Pipette accuracy
Least accurate when measuring a volume at the bottom of its range.
Burettes typical volume range
Between 10-100 mL.
Burettes measurement range
Accurately measure volumes between 10-100 mL.
25 mL burette accuracy
±0.06 mL.
Erlenmeyer flasks measurement accuracy
Not used for precise measurements as their graduations provide only an approximate measure within 5% of the target volume.
Erlenmeyer flasks capacity range
From 25 mL to 4 L.
Common laboratory balances accuracy
Measure to the hundredth of a gram.
Typical temperature for biology experiments
37°C, normal human body temperature.
Room temperature in lab
Approximately 22°C.
Ultralow freezer temperature
-80°C or a liquid nitrogen tank at -196°C.
Storage temperature for temperature-sensitive reagents
4°C in a refrigerator or -20°C in a freezer.
Standard autoclave conditions
121°C and 15-20 PSI to kill bacteria and spores.
Autoclave purpose
Sterilizing liquids, containers, and instruments by increasing pressure to raise the boiling point of water beyond 100°C.
Organizations with BSL-2 laboratories
Biotechnology companies, research universities, hospitals, and national labs.
Agents in BSL-1 laboratories
Agents not typically associated with human disease
Cleanroom protective clothing
Hood, face mask, gloves, boots, and coveralls or a cleanroom gown.
PPE in BSL-1 laboratories
Lab coat, gown, or uniform; eyewear for splashing risks; gloves.
Examples of agents in BSL-2 Labs
Hepatitis B & C viruses, HIV, Candida albicans.
BSL-1 laboratory precautions
Do not reuse gloves; wash hands before leaving; prohibit eating, drinking, applying cosmetics, or handling contact lenses.
Additional PPE in BSL-2 laboratories
Use of biological safety cabinets (BSCs) for splash-prone procedures; eye and face protection.
BSL-2 laboratory precautions
Limit access to trained personnel only; post clearly labeled hazard signs; dispose of needles and syringes in puncture-resistant containers.
Examples of agents in BSL-3 laboratories
Yellow fever virus, Zika virus, West Nile virus.
Additional PPE in BSL-3 laboratories
Use of BSCs for all open manipulations of agents.
BSL-3 laboratory precautions
Controlled access; located in sealed areas with negative airflow; exhaust air must not be recirculated.
BSL-4 laboratory precautions
Separate or isolated building; dedicated supply/exhaust systems with HEPA filtration.
Additional PPE in BSL-4 laboratories
Full-body positive-pressure suits; shower upon exiting the laboratory.
Molarity
Equal to normality for HCl because HCl only donates one H+ ion per molecule.
Avogadro’s constant
6.02 × 10²³, the number of molecules in one mole of a substance.
Water for making solutions
Distilled or ultrapure water from a purification system like Millipore.
Most accurate vacuum-assisted pipet
Volumetric pipets.
Volumetric pipets composition and shape
Made of glass and have a recognizable shape.
10 mL Class A volumetric pipet accuracy
Accurate to within 0.02 mL.
Types of graduated pipettes
Mohr and serological.
Difference between Mohr and serological pipets
Mohr pipets have a dead volume and should not be emptied beyond the zero mark, while serological pipets deliver the entire contents.
Laboratory balance precision
Frequently measure to the thousandth or ten thousandth.
Temperature measurement in molecular biology lab
Measured in Celsius.
pH measurement in lab
By rinsing electrodes with distilled water and placing them in the solution to be measured.
BSL-1 laboratory pathogens
Microorganisms like E. coli HB101 that do not cause disease in healthy people.
Common laboratory types
Most community colleges have BSL-1 laboratories, but some may also have BSL-2 laboratories.
Laboratory requirement for tissue culture work
A BSL-2 laboratory.
Risk level of BSL-3 and BSL-4 laboratories
Handle pathogens like the Ebola virus (BSL-4) that can cause severe or fatal diseases.
BSL-3 and BSL-4 laboratory locations
Most are found in government facilities.
Key component of a cleanroom
A High Efficiency Particulate Air (HEPA) filter.
Air delivery in cleanroom
All air must pass through a HEPA Filter.
Agents in BSL-2 laboratories
Agents with moderate health hazards.
Agents in BSL-3 laboratories
Agents with significant or lethal risks via inhalation.
Agents in BSL-4 laboratories
Agents with high risk of untreatable or life-threatening diseases.
Examples of agents in BSL-4 laboratories
Ebola virus, viral hemorrhagic fever.
1 M solution of H2SO4
Equal to 2 N because sulfuric acid (H2SO4) donates two H+ ions to the solution.
1 M CaCl2 preparation
Use a powder funnel to transfer 110.98 g of CaCl2 crystals to a 1 L volumetric flask.
Mole of a substance
Has the same number of molecules as 12g of carbon.
Unsuitable water for laboratory applications
Distilled Water.
Example of agents in BSL-1 labratories
e.g., E. coli DH5α, Saccharomyces cerevisiae
