Question is ⇒ Biomass concentrations during fermentation is, Options are ⇒ (A) diluting the samples to optical density less than 0.3, (B) monitored by controlling the changes in biomass concentrations, (C) considering that optical density is proportional to the surface area of the biomass in the sample, (D) all of the above, (E) , Leave your comments or Download question paper.

Question is ⇒ Biomass concentrations during fermentation is, Options are ⇒ (A) diluting the samples to optical density less than 0.3, (B) monitored by controlling the changes in biomass concentrations, (C) considering that optical density is proportional to the surface area of the biomass in the sample, (D) all of the above, (E) , Leave your comments or Download question paper. Previous question Next question


Q1.	Biomass concentrations during fermentation is
A.	diluting the samples to optical density less than 0.3 [Wrong Answer]
B.	monitored by controlling the changes in biomass concentrations [Wrong Answer]
C.	considering that optical density is proportional to the surface area of the biomass in the sample [Wrong Answer]
D.	all of the above [Correct Answer]
View Answer 1 -1 Explanation:- Answer : D Discuss it below : !! OOPS Login [Click here] is required to post your answer/result Help other students, write article, leave your comments

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⇒ The height to diameter ratio (H/D) for the column fermenters is
<3
>3
<1.5
>1.5

⇒ The maximum specific growth rate (μ_m) of an organism in batch culture is equal to slope of a plot of
In [biomass] against time for exponential phase data only
In [biomass] against time
biomass against time
biomass against time for stationary phase data only

⇒ The monod model predicts that the specific growth rate
will increase with the concentration of the growth limiting substrate until it reaches a maximum value
will decrease with the concentration of the growth limiting substrate
will increase with the concentration of the growth limiting substrate
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⇒ Heat transfer rates (per unit volume) will be lowest in
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Continuous air lift bioreactor
Continuous packed bed reactor
Continuous fluidized bed bioreactor

⇒ The height to diameter ratio (H/D) for the tank fermenters is
<3
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<1.5
>1.5

⇒ The specific growth rate is affected by
sabstrate concentration
product concentration
oxygen supply
all of these

⇒ An internal draft tube is preferrred to an external draft tube because
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⇒ The increased air flow rate in bubble column fermenter can cause excessive foaming and high retention of air bubbles in the column which
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⇒ In the death phase
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⇒ When intracellular enzymes of whole cells are to be used in a bio-conversion process, it is often necessary to____________the cells.
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deceleration of growth and division rate after the growth rate reaches a maximum
acceleration of growth and division rate after the growth rate reaches a maximum
deceleration of growth and division rate after the growth rate reaches a minimum

⇒ The diameter of the baffles in a standard stirred tank bioreactor ranges from
1/10^th - 1/12^th of the tank diameter
1/3^rd - 1/4^thof the tank diameter
1/15^th - 1/20^th of the tank diameter
1/20^th - 1/25^th of the tank diameter

⇒ A culture in a closed vessel to which no additional medium is added and from which no waste products are removed is called a __________ culture.
continuous
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⇒ Which of the following is an example of a mathematical model?
Volume of cuboid = length x breadth x height
The Monod Model
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⇒ Population doubling time, t_d can be expressed as (where μ is the specific growth rate.)
log2/μ
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⇒ The optical density sometimes drops during the lag phase because
cells tend to grow without dividing leading to a decrease in the surface area to volume ratio
of fast cell growth causing them to fill up with DNA
cells swell up with water
cells swell up with RNA

⇒ Biomass concentrations during fermentation is
diluting the samples to optical density less than 0.3
monitored by controlling the changes in biomass concentrations
considering that optical density is proportional to the surface area of the biomass in the sample
all of the above

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remains constant throughout the process
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changes during the fermentation
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⇒ The bubble column fermenter is usually limited to
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anaerobic fermentations
Both (a) and (b)
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C_n₀ = C_n exp[μ (t - t₀)]
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C_n₀ / C_n = (1/μ)exp(t-t₀)