1. After the first subculture, the primary culture is called ________________
a) clone
b) daughter cells
c) cell debris
d) cell Line
Explanation: After the first subculture, the primary culture is called Cell line or Sub-clone. The cells lines derived from the primary cell cultures usually have a short life span, finite cell culture. Some cell lines continue to proliferate through transformations, continuous cell lines.
2. A typical cell culture environment consists of various _______________ like amino acids, carbohydrates, vitamins and minerals.
a) nutrients
b) gases
c) hormones
d) growth factors
Explanation: A typical cell culture environment consists of various essential nutrients along with gases (e.g., O2, CO2), and appropriate physiochemical conditions (pH, osmotic pressure, and temperature). Even hormones and growth factors are an essential component of any cell culture environment.
3. If cells need to be stored, they must be treated with an appropriate protective agent (like H2SO4) and stored at temperatures above 0° C.
a) True
b) False
Explanation: If cells need to be preserved for sub-culturing later, then they must be treated with an appropriate protective agent (e.g. DMSO or glycerol) and stored at temperatures below -130°C. This is called Cryopreservation.
4. Cell cultures can be categorized into 5 types based on the shape of cells.
a) True
b) False
Explanation: Cell cultures can be categorized into 3 types based on cell shape or morphology. The first type are fibroblast-like cells, have elongated shapes. The second type is epithelial-like cells, polygonal in shape. The third type is lymphoblast-like cells, spherical in shape.
5. Which of the following is considered as the most basic level of safety?
a) BSL-1
b) BSL-5
c) BSL-8
d) BSL-10
Explanation: Biosafety level 1 (BSL-1) is considered as the most basic level of safety followed in the laboratories handling cell cultures, this is appropriate for the agents that are not harmful to humans in general.
6. __________ is appropriate for agents that might pose a greater individual risk.
a) BSL-4
b) BSL-3
c) BSL-2
d) BSL-9
Explanation: Biosafety level 2 (BSL-2) is considered appropriate for the agents that cause variable severity of a disease which is acquired by ingestion or membrane interactions. Biosafety level 3 (BSL-3) is considered appropriate for the agents that might cause lethal infections through aerosol transmissions. Biosafety level 4 (BSL-4) is considered appropriate for the agents that cause life-threatening diseases through aerosol transmissions, these diseases have no cure.
7. Which of the following lab equipment is used for maintaining a sterile environment while working?
a) Cell Culture hood
b) Centrifuge
c) Inverted microscope
d) Magnetic Stirrer
Explanation: Cell Culture hoods help in maintaining aseptic or sterile work environment as well as help in the containment of the aerosols generated by various microbial procedures.
8. Which of the following lab equipment is used for maintaining cell cultures?
a) Petri-plate
b) Incubator
c) pH-meter
d) Water bath
Explanation: Incubators are a device that allows the maintenance of cell cultures, at an optimal temperature, pressure and helps maintain the appropriate amounts of various gases (O2, CO2).
9. There are 3 Classes of cell culture hood.
a) True
b) False
Explanation: There are 3 classes of culture hoods, Class I hoods offer protection to laboratory personnel, but not against contamination. Class II hoods are designed for work involving BSL-1, 2, and 3 materials, these are used for handling hazardous materials. Class III hoods are designed for work involving BSL-4 materials, these are air-tight and provide the highest level of protection to the laboratory personnel as well as the environment.
10. ________ was the first continuous cell line.
a) HeLa
b) 3T3
c) HEK 293
d) A549
Explanation: HeLa cell line is an immortal cell line used in scientific research. It’s been the oldest and most commonly used human cell line. The cells were derived from cervical cancer cells in the year 1951 on 4th of February from Henrietta Lacks (a patient who died on October 4, 1951).