Discussion
Home ‣ Biochemical Engineering ‣ Fermentation Reactors Comments
- Question
Which of the statement is true for continuous reactor at steady state?
Options- A. The rates of biomass, substrate and product concentrations are zero
- B. Biomass, substrate and product concentrations are zero
- C. Biomass, substrate and product concentrations do not change with time
- D. Biomass, substrate and product concentrations change with time
- Correct Answer
- Biomass, substrate and product concentrations do not change with time
- 1. Saccharomyces cerevisiae is being grown in a chemostat converts glucose to biomass, ethanol, glycerol and carbon dioxide. At steady state, the concentration of glucose, biomass, ethanol and glycerol will
Options- A. decrease with time
- B. increase with time
- C. be constant
- D. change randomly with time Discuss
- 2. In fed-batch fermentation, mass of substrate utilized is calculated using the relationship
Options- A. initial mass of substrate in the reactor + final mass of substrate in the reactor + flow rate x [substrate in the feed]
- B. initial mass of substrate in the reactor - final mass of substrate in the reactor + flow rate x [substrate in the feed]
- C. initial mass of substrate in the reactor + final mass of substrate in the reactor - flow rate x [substrate in the feed]
- D. initial mass of substrate in the reactor + final mass of substrate in the reactor - flow rate Discuss
- 3. When two populations compete for a single growth limiting substrate in a continuous fermenter, which organism would not be washed out?
Options- A. Organism maintaining the highest substrate concentration
- B. Organism maintaining the lowest substrate concentration
- C. Both (a) and (b)
- D. Organism maintaining the moderate substrate concentration Discuss
- 4. A fed-batch reactor initially contains 2 litre of medium. If it was fed at 1 litre per hour, then after 10 hours, the volume of the reactor will be
Options- A. 1 litre
- B. 2 litre
- C. 3 litre
- D. 13 litre Discuss
- 5. If biomass yields are constant, then the biomass productivity of a culture grown in continuous reactor will
Options- A. always decrease with dilution rate
- B. increase with dilution rate until washout
- C. remain constant irrespective of the dilution rate
- D. decrease with dilution rate until washout Discuss
- 6. Which of the following is used to calculate mass of substrate in the reactor?
Options- A. Flow rate x substrate concentration in the reactor
- B. Volume of reactor x substrate concentration in reactor
- C. Flow rate x mass of reactor
- D. Volume of reactor x Flow rate Discuss
- 7. Mixing in an anaerobic sludge blanket reactor is due to
Options- A. rapid change in water temperatures throughout the reactor
- B. release of gases by the microbial populations
- C. swimming of microbes
- D. none of the above Discuss
- 8. Fluidized bed bioreactors provide higher mass transfer rates than packed bed bioreactors because
Options- A. mixing is higher in fluidized bed bioreactors
- B. particles move with the fluid in a fluidized bed bioreactor
- C. immobilized particles are smaller in the fluidized bed bioreactors
- D. all of the above Discuss
- 9. Low dissolved oxygen concentrations leads to
Options- A. low biomass yields
- B. high biomass yields
- C. no effect on biomass yields
- D. none of the above Discuss
- 10. In aerobic yeast fermentation for production of citric acid from alkanes using a fed-batch culture, why alkanes are slowly fed to the yeast?
Options- A. Citric acid is toxic to the cells
- B. Alkanes cause foaming
- C. Fast addition of alkanes will inhibit the cells and reduce oxygen transfer rates
- D. Fast addition of alkanes will cause the cells to grow too quickly Discuss
Fermentation Reactors problems
Search Results
Correct Answer: be constant
Correct Answer: initial mass of substrate in the reactor - final mass of substrate in the reactor + flow rate x [substrate in the feed]
Correct Answer: Organism maintaining the lowest substrate concentration
Correct Answer: 2 litre
Correct Answer: increase with dilution rate until washout
Correct Answer: Volume of reactor x substrate concentration in reactor
Correct Answer: release of gases by the microbial populations
Correct Answer: particles move with the fluid in a fluidized bed bioreactor
Correct Answer: low biomass yields
Correct Answer: Fast addition of alkanes will inhibit the cells and reduce oxygen transfer rates
Comments
There are no comments.Programming
Copyright ©CuriousTab. All rights reserved.