Fermentation Technology Multiple Choice Questions on “Microbial Growth Kinetics – FedBatch Culture”.
1. The Fed-batch culture is a/an ______ culture system.
A. Open
B. Closed
C. Isolated
D. Semi-closedid5fcf61a751315″
Answer: D
Clarification: The Fed-batch culture is a closed culture system where the nutrient media is prepared and it is inoculated with culture organism and then is incubated for a particular time. The batch culture is a closed system and continuous culture is an open system.
2. Who introduced the term “Fed-Batch”?
A. Burrow et al.
B. Bu’Lock et al.
C. Yoshida et al.
D. Maniatis et al.id5fcf61a751338″
Answer: C
Clarification: The term “Fed-Batch” was introduced by Yoshida et al. to describe the cultures which are fed continuously or sequentially without the removal of culture fluid.
3. Which of the following is a type of Fed-Batch culture?
A. Variable volume
B. External Feedback
C. Internal Feedback
D. Chemostatid5fcf61a751353″
Answer: A
Clarification: There are two types of Fed-Batch culture: Variable-volume fed-batch culture and fixed-volume fed-batch culture. The external feedback, internal feedback, chemostat are the types of continuous fermentation.
4. Which scientist(s) described the kinetics of variable-volume fed-batch culture?
A. Dunn and Mor
B. Maniatis et al.
C. Van’t Hoff
D. Maxwellid5fcf61a751369″
Answer: A
Clarification: The kinetics of variable-volume fed-batch culture have been developed by Dunn and Mor in 1975 and Pirt in 1974, 1975, 1979.
5. What happens in a Quasi-Steady state?
A. Specific growth increases
B. Specific growth decreases
C. Specific growth becomes constant
D. Specific growth becomes zeroid5fcf61a751373″
Answer: B
Clarification: In a Quasi-steady state, specific growth gradually decreases. It is a state where all the variables become constant. The Quasi-state approximation is useful in studying the kinetics of certain chemical reactions.
6. What is the condition for a Quasi-Steady state?
A. µ = 0
B. µ = D
C. D = F
D. µ = Fid5fcf61a75137b”
Answer: B
Clarification: Although the total biomass in the culture increases with time, cell concentration(x) remains virtually constant, that is (dx/dt) = 0 and therefore µ = D (approx.). This situation is termed as a Quasi-Steady State.
7. In Variable-volume fed-batch culture, the broth volume remains almost the constant.
A. True
B. Falseid5fcf61a751384″
Answer: B
Clarification: In Variable-volume fed-batch culture, volume changes with fermentation time due to the substrate feed. That is why the name is variable-volume fed-batch culture. Whereas, in fixed-volume fed-batch culture, volume remains the same.
8. Which of the following does not include in the range of fermentation processes?
A. Microbial Enzymes
B. Microbial metabolites
C. Biotransformation
D. Recombinant DNAid5fcf61a75138e”
Answer: D
Clarification: The range of fermentation processes includes microbial enzymes, microbial metabolites, biotransformation, recombinant protein, microbial cells. Recombinant DNA is produced by rDNA technology.
9. Which of the following was used in the production of bakers’ yeast?
A. Batch culture
B. Continuous culture
C. Fed-Batch culture
D. Solid state cultureid5fcf61a751396″
Answer: C
Clarification: Fed-Batch culture was used in the production of bakers’ yeast as early as 1915. Bakers’ yeast is a yeast useful in the production of a variety of bread in the baking industry. Saccharomyces cerevisiae is known as Bakers’ yeast, is useful for the production of yeast and alcohol.
10. Which of the following is correct with respect to Fermentation?
A. A process involving the mass culture of micro-organisms
B. It is a fast process
C. Fermented food products are always healthy
D. Oxygen is produced during fermentationid5fcf61a75139f”
Answer: A
Clarification: Fermentation is a slow process involving the mass culture of micro-organisms, production of alcoholic beverages, food spoilage, growth dependent on substrate-level phosphorylation. Sometimes it can lead it gastric cancer.
11. In fixed-volume fed-batch culture, volume changes with fermentation time due to the substrate feed.
A. True
B. Falseid5fcf61a7513a7″
Answer: B
Clarification: In fixed-volume fed-batch culture, the broth volume remains almost the constant. Hence, the name is fixed-volume. Whereas, in variable-volume fed-batch culture, the volume keeps on changing.
12. Who developed a method for the optimization of the fed-batch system?
A. Shioya
B. Queener
C. Swartz
D. Wakiid5fcf61a7513b0″
Answer: A
Clarification: Shioya in 1990 developed a method for the optimization of fed-batch culture based on the relationship of µ and qp.
13. Cyclic Fed-Batch culture has been used for the production of _______
A. Bovine serum albumin
B. Penicillin
C. Human serum albumin
D. Cheese Productionid5fcf61a7513b8″
Answer: C
Clarification: Cyclic fed‐batch culture has been used for the production of human serum albumin. Human Serum Albumin is an organic component of blood plasma, which is used to maintain osmotic pressure of blood.
14. What is the unit of substrate feed rate (G)?
A. dm3
B. dm3 h-1
C. g dm-3 h-1
D. g dm3id5fcf61a7513cc”
Answer: C
Clarification: The unit of substrate feed rate G is g dm-3 h-1 which is given by the equation,
(dx/dt) * Y = G where Y is the yield factor.
15. The feed solution in fed-batch culture is highly concentrated to _______
A. avoid dilution of the bioreactor
B. maintain low cell density in bioreactor
C. avoid lag phase
D. increase productivityid5fcf61a7513d4″
Answer: A
Clarification: The feed solution in fed-batch culture is highly concentrated to avoid dilution of the bioreactor and to reach high cell density in a bioreactor.