250+ MCQs on Types of Bioreactors and Answers

Fermentation Technology Multiple Choice Questions on “Types of Bioreactors”.

1. In World War II, the fermentation was used for the production of _____________
A. Alcohol
B. Antibiotics
C. Wine
D. Beerid5fdc77a5cdf9b”

Answer: B
Clarification: In World War Two, the bioreactor was used in the production of antibiotics. The development of fermentation came after the 1940s onwards, till then it was used in the production of potable alcohol.

2. The small-scale bioreactors have volume of __________
A. 5-10 litres
B. 10-20 litres
C. 1-10 litres
D. 1-20 litresid5fdc77a5cdfcf”

Answer: D
Clarification: The small-scale bioreactors normally have a volume of 1-20 litres. The bioreactor is used for a number of purposes, scale-up and scale-down studies, clone selection, medium development, process development, etc.

3. The bioreactor is not capable of ______________
A. Producing aseptic conditions
B. Meeting containment regulations
C. Controlling pH
D. Produce electricityid5fdc77a5cdfdf”

Answer: D
Clarification: The bioreactor is not capable of producing electricity. However, it is capable of producing aseptic conditions for longer periods of time, meeting containment regulations, monitoring or controlling pH, temperature, DO, etc.

4. Which of the following fermenters are characterized by height to diameter ratio?
A. Tower fermenter
B. Airlift fermenter
C. Hollow fibre
D. Perfusion bioreactorid5fdc77a5cdfeb”

Answer: A
Clarification: Tower fermenters are the vessels which are characterized by a high height-to-diameter ratio anywhere around 6:1 to 15:1. Aeration is provided by gas sparging via a sample sparger near the fermenter base.

5. In which of the following fermenters the impellers are replaced by the constant flow of gas?
A. Airlift fermenter
B. Tower fermenter
C. Hollow fibre
D. Perfusion bioreactorid5fdc77a5cdff6″

Answer: A
Clarification: In airlift fermenters, the impellers, motors, the driveshaft is replaced by a constant flow of gas introduced into a riser tube. It may also be provided with baffles for improving the mixing efficiency.

6. Which of the following is used to grow anchorage-dependent cells?
A. Airlift fermenter
B. Tower fermenter
C. Hollow fibre chamber
D. Perfusion bioreactorid5fdc77a5ce000″

Answer: C
Clarification: Hollow fibre chambers are used to grow anchorage-dependent cells. It consists of a bundle of fibres and the cells grow with extra capillary spaces within a cartridge.

7. Which of the following bioreactor consists of a vessel replaced by a multilayered bag?
A. Single Use bioreactors
B. Perfusion bioreactors
C. Airlift bioreactor
D. Tower bioreactorid5fdc77a5ce00a”

Answer: A
Clarification: A single-use bioreactor consists of a vessel replaced by a multi-layered bag. It meets all the criteria for a product in contact with a biological process like leaching or chelating.

8. What is the function of carbon in stainless steel?
A. Improves resistance to corrosion
B. Improves ductility
C. Reduces sensitization
D. Improves halogen resistanceid5fdc77a5ce016″

Answer: C
Clarification: The carbon reduces the sensitization when present in stainless steel. It is a maximum of 0.03 % which prevents the precipitation of carbon during welding.

9. The Borosilicate glass does not contain ________
A. SiO2
B. B2O3
C. Al2O3
D. KH2PO4id5fdc77a5ce020″

Answer: D
Clarification: Borosilicate glass is chemically inert, easy to clean and robust. The glass is made up of SiO2 81 %, B2O3 13 % ,NaO2 + K2O 4 % and Al2O3 2 %. It has to meet the criteria for the thickness of the glass, the number of air bubbles within the glass and the number of bubbles on the surface.

10. Which of the following class consists of microorganisms which are not causative agents?
A. EFB Class 1
B. EFB Class 2
C. EFB Class 3
D. EFB Class 4id5fdc77a5ce02b”

Answer: A
Clarification: Microorganisms that have never been identified as causative agents of disease in man are termed as harmless microorganisms and belong to EFB Class 1 and do not offer a threat to the environment.

11. Which of the following class consists of microorganisms which are causing disease in man and are hazardous to workers?
A. EFB Class 3
B. EFB Class 1
C. EFB Class 2
D. EFB Class 4id5fdc77a5ce035″

Answer: C
Clarification: Microorganisms that may cause disease in man and are, therefore, hazardous to laboratory workers. They do not spread in the environment. Prophylactics are used for the treatment. They are called low-risk microorganisms.

12. EFB Class 4 consists of ___________
A. Low-risk microorganisms
B. High-risk microorganisms
C. Medium-risk microorganisms
D. Environmental-risk microorganismsid5fdc77a5ce03f”

Answer: B
Clarification: EFB Class 4 consists of High-risk microorganisms. These are microorganisms that cause severe illness to the microorganisms and are very hazardous to people at work. No effective treatment is available for this class.

13. Which of the following class of microorganisms causes less threat to a man?
A. Low-risk microorganisms
B. High-risk microorganisms
C. Medium-risk microorganisms
D. Environmental-risk microorganismsid5fdc77a5ce049″

Answer: D
Clarification: Microorganisms cause less threat to man and are very hazardous to the environment. They are also called as environmental-risk microorganisms and are responsible for high economic losses.

14. In a bubble column reactor, the mass transfer depends on the size of the bubble.
A. True
B. Falseid5fdc77a5ce053″

Answer: A
Clarification: In a bubble column reactor, the hydrodynamics and mass transfer depends on the size of the bubbles and their release from the sparger. It is used in the production of Bakers’ yeast, Beer, and Vinegar. It is also used in aeration and treatment of wastewater.

15. Bubble column reactor provides better mixing than airlift reactors.
A. True
B. Falseid5fdc77a5ce05d”

Answer: B
Clarification: The airlift bioreactors provide better mixing than bubble column reactors. The airlift bioreactors provide a configuration of a greater degree of stability to liquid flow compared with bubble columns. Therefore, higher gas flow rates can be used without incurring operating problems like spray formation.