1) During the course of fed-batch operation the volume of the broth continuously:
Doesn’t undergo any change.
2) Arrange the growth processes in the order they occur during a fed-batch operation: (i) lag phase, (ii) death phase, (iii) deceleration phase, (iv) stationary phase, (v) exponential growth phase:
(i), (ii), (iii), (iv), (v)
(i), (iv), (iii), (ii), (v)
(iii), (i), (iv), (v), (ii)
(i), (v), (iii), (iv), (ii)
3) Name the phase which is a period of adaptation of the cells to the new environment :
Exponential Growth Phase
4) What can result in starting of the Deceleration Phase during a fed-batch operation?
(i) Substantial depletion of one or more essential nutrients.
(ii)Accumulation of toxic by-products.
Only (i) alone.
Only (ii) alone.
Both (i) and (ii).
Neither (i) nor (ii).
5) Which condition marks the beginning of stationary phase?
Growth rate of cells becomes negative.
Growth rate of cells becomes positive.
The net growth rate of cells becomes zero.
None of the above.
6) Production of lactic acid by fermentation is a classic example of:
Non-growth associated products.
Growth associated products.
Mixed growth associated products.
None of the above.
7) Non-growth associated products like penicillin are produced:
When specific rate of product formation is proportional to the specific rate of growth.
During deceleration phase.
Just after the death phase when intracellular proteins are released into medium by the dead cells.
During stationary phase.
8) Which of the following time profile is fundamentally incorrect and shouldn’t be observed during the course of experiment:
Volume of fed-batch increases continuously.
Product concentration increases with decreasing slope.
Specific growth rate increases continuously.
Substrate concentration decreases with time.
9) During the formation of growth associated products, the rate of substrate consumption depends upon:
Cell maintenance only.
Cell maintenance + product formation
Product formation + biomass production.
Sum of cell maintenance, product formation and biomass production.
10) In a single fed-batch operation:
After fermentation has reached a stage, some culture is removed from vessel and replaced by fresh medium.
Volume decreases and specific growth rate increases.
The growth medium is added during the process and no culture is removed till the end.
None of these