Fermentation Reactors

Question: Toxins accumulated in a reactor can lead to low biomass yields probably due to which of the following?
[A].

NAD+ is diverted away from homeostasis to anabolism

[B].

ATP is diverted away from homeostasis to anabolism

[C].

NAD+ is diverted away from anabolism to homeostasis

[D].

ATP is diverted away from anabolism to homeostasis

Answer: Option D

Explanation:

No answer description available for this question.

Question: When the product formation is approximately equal to the rate of cell growth, the pattern of product formation is termed as
[A].

uncoupled

[B].

growth associated

[C].

non-growth associated

[D].

metabolically uncoupled

Answer: Option B

Explanation:

No answer description available for this question.

Question: 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

Answer: Option C

Explanation:

No answer description available for this question.

Question: The toxicity of organic acids to cells
[A].

enhances as the pH falls

[B].

reduces as the pH falls

[C].

is not affected by pH

[D].

is highest at pH 7.0

Answer: Option A

Explanation:

No answer description available for this question.

Question: Production of organic acids in batch culture is generally growth associated phase followed by non-growth associated production. The probable reason for this is that
[A].

organic acids uncouple catabolism from anabolism

[B].

biomass yields increase as the fermentation proceeds

[C].

organic acids are secondary metabolites

[D].

high concentrations of organic acid promote the growth of the microbial population

Answer: Option A

Explanation:

No answer description available for this question.

Question: A microorganism which is subjected to the Crabtree effect is most likely to
[A].

ferment in the presence of low concentrations of sugar and dissolved oxygen

[B].

respire in the presence of low sugar and high dissolved oxygen concentrations

[C].

ferment in the presence of high concentrations of sugar and dissolved oxygen

[D].

respire in the presence of high sugar and low dissolved oxygen concentrations

Answer: Option C

Explanation:

No answer description available for this question.

Question: Which of the following organisms will continue their metabolism at high substrate concentrations?
[A].

Pseudomonas aeruginosa

[B].

Saccharomyces cerevisiae

[C].

Bacillus subtilis

[D].

Escherichia coli

Answer: Option A

Explanation:

No answer description available for this question.

Question: Formation of end product by Lactococcus lactis will become non-growth associated as lactic acid accumulates because
[A].

cells will redirect ATP to anabolism

[B].

cells will redirect NAD+ to anabolism

[C].

cells will redirect ATP to facilitate the diffusion of lactic acid and H+ out of the cells

[D].

cells will redirect ATP to the active transport of lactic acid and H+ out of the cells

Answer: Option D

Explanation:

No answer description available for this question.

Question: Which of the following is best described as secondary metabolite?
[A].

Acetic acid produced from the oxidation of ethanol

[B].

Ethanol from the fermentation of glucose

[C].

Penicillin

[D].

Citric acid from the partial oxidation of glucose

Answer: Option C

Explanation:

No answer description available for this question.

Question: If biomass yields are constant, then the biomass productivity of a culture grown in continuous reactor will
[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

Answer: Option B

Explanation:

No answer description available for this question.