200 Best MCQs on Fermentation Reactors- biochemical engineering
Q25). A chemostat has a liquid volume of 2 litres and is being fed at a rate of 4 litres per hour. Dilution rate for this reactor will be
a).2 litres
b).2 litres per hour
c).2 h^-1
d).4 litres per hour
Correct Answer:
2 h^-1
Explaination:
Q26). Mixing per unit volume is observed to be poorest in
a).continuous packed bed reactor
b).continuous fluidized bed bioreactor
c).continuous airlift bioreactor
d).none of the above
Correct Answer:
continuous packed bed reactor
Explaination:
Q27). A culture system with constant environmental conditions maintained through continual provision of nutrient and removal of wastes is called __________ culture system.
a).continuous
b).batch
c).fed-batch
d).semi continuous
Correct Answer:
continuous
Explaination:
Q28). The main reason for production of antibiotics in fed batch reactors is
a).the presence of precursors is often toxic to the cells
b).higher yields when cells enter the stationary phase
c).higher yields when cell growth slows
d).all of the above
Correct Answer:
all of the above
Explaination:
Q29). Fed batch reactors is used to produce vinegar because
a).it can maintain low ethanol concentrations
b).it can maintain low acetic acid concentrations
c).acetic acid bacteria tend to ferment at high ethanol concentrations
d).all of the above
Correct Answer:
it can maintain low ethanol concentrations
Explaination:
Q30). When a culture of fermenting yeast becomes metabolically uncoupled, ethanol
a).becomes a secondary metabolite
b).production becomes growth associated
c).production becomes non-growth associated
d).becomes a growth nutrient
Correct Answer:
production becomes non-growth associated
Explaination:
Q31). Mixing profiles closest to plug flow are observed in
a).continuous packed bed reactor
b).stirred tank reactor with biomass recycles
c).continuous fluidized bed bioreactor
d).all of these
Correct Answer:
continuous packed bed reactor
Explaination:
Q32). Unsteady state mass balance for dynamic model of continuous stirred tank reactor (CSTR) is
a).time rate of total amount in rector = rate of addition to reactor -rate of removal + rate of formation
b).total amount in rector = rate of addition to reactor – rate of removal + rate of formation
c).rate of total amount in rector = rate of addition to reactor – rate of removal + rate of formation
d).none of the above
Correct Answer:
time rate of total amount in rector = rate of addition to reactor -rate of removal + rate of formation
Explaination: