Questions and answers for exam Preparation

MCQs

Total Questions : 114 | Page 1 of 12 pages

Question 1. The production of an amylase from starch by Aspergillus niger is often performed in a fed batch fermenter. This is due to the reason that

fed-batch reactor can be used to minimize starch concentrations and prevent niger from fermenting
fed-batch reactor can be used to minimize starch concentrations and thus reduce the viscosity of the medium
continuous reactor can be used to minimize starch concentrations and their inhibitory effects
all of the above

Discuss Question

Answer: Option B. -> fed-batch reactor can be used to minimize starch concentrations and thus reduce the viscosity of the medium
Answer: (b).fed-batch reactor can be used to minimize starch concentrations and thus reduce the viscosity of the medium

Question 2. The fastest route of NADH reoxidation is

aerobic respiration
anaerobic respiration
fermentation
decomposition

Discuss Question

Answer: Option C. -> fermentation
Answer: (c).fermentation

Question 3. In plug flow tubular reactor the axial velocity profile on cross-section will be

constant
varying with time
non-linear
power function of time

Discuss Question

Answer: Option A. -> constant
Answer: (a).constant

Question 4. In fed batch bioreactor modelling, the rate of change in the bioreactor volume is assumed to be equal to

flow rate
initial volume
volume of solids in the reactor
none of these

Discuss Question

Answer: Option A. -> flow rate
Answer: (a).flow rate

Question 5. Monoclonal antibodies are typically produced in fed batch reactors because

hybridoma cells ferment at high maltose concentrations
hybridoma cells yield higher lactate at high glucose concentrations
hybridoma cells respire at high glucose concentrations
none of the above

Discuss Question

Answer: Option B. -> hybridoma cells yield higher lactate at high glucose concentrations
Answer: (b).hybridoma cells yield higher lactate at high glucose concentrations

Question 6. Which of the following is not correct with regards to continuous cultures?

The major industrial scale application of continuous cultures is in waste water treatment
Mutation and contamination present a major risk to the operation of continuous cultures for the production of metabolites
The continuous cultures is very useful for the production of pharmaceuticals
Continuous cultures have an advantage that they do not need to shut down as regularly as batch culture reactor

Discuss Question

Answer: Option C. -> The continuous cultures is very useful for the production of pharmaceuticals
Answer: (c).The continuous cultures is very useful for the production of pharmaceuticals

Question 7. A fed-batch reactor containing 2 litre of medium and 0.1 g.l¹ of biomass is fed with a medium containing 1 g.l¹ of substrate at 1 litre per hour. If after 10 hours, the concentration of biomass in the reactor was 0.2 g.l¹, then the biomass produced during the 10 hour period is

1.5 g
2.2 g
3.0 g
6.0 g

Discuss Question

Answer: Option B. -> 2.2 g
Answer: (b).2.2 g

Question 8. In a plug flow reactor, the highest concentration of substrates is exposed to the cells that

are near the effluent or exit of the reactor
are in the mid way along the reactor
are located near entrance of feed
are near the wall of the reactor

Discuss Question

Answer: Option C. -> are located near entrance of feed
Answer: (c).are located near entrance of feed

Question 9. In an activated sludge process, the biomass is recycled to

increase the efficiency of the process
reduce sludge volumes
increase the concentration of cells
all of the above

Discuss Question

Answer: Option D. -> all of the above
Answer: (d).all of the above

Question 10. A strain of Escherichia coli has a maximum specific growth rate of 0.8 h¹ on a glucose based medium. If this organism is being grown in a chemostat with a dilution rate of 1.2 h¹, then at steady state the concentration of E. coli in the same medium will