Biochemical Engineering

Question: Reynolds number for laminar flow over a plate should be less than
[A].

500 mm

[B].

5 x 10-5

[C].

5 x 105

[D].

5 m

Answer: Option C

Explanation:

No answer description available for this question.

Question: Which of the following describes the detrimental effect of bubbles on animal cells?
[A].

Cells trapped on the surface of bubbles can be damaged when the bubbles explode, releasing their pressure and surface energies

[B].

Cells trapped in the moving foam can be dragged apart by the bubbles

[C].

Both (a) and (b)

[D].

Bubbles can explode in the liquid medium causing the release of ultraviolet radiation

Answer: Option C

Explanation:

No answer description available for this question.

Question: Filamentous fungal cells are more shear sensitive than bacterial cells because of
[A].

the presence of citin in cell walls of filamentous fungi

[B].

larger in size than bacterial cells and therefore are more susceptible to shear forces

[C].

fungal cells are much larger than bacterial cells

[D].

all of the above

Answer: Option D

Explanation:

No answer description available for this question.

Question: The approach which is commonly used to determine the level of damage to animal cells in a culture medium is to monitor
[A].

the concentration of lactate in the medium

[B].

the level of lactate oxidase activity in the medium

[C].

the level of lactate dehydrogenase activity

[D].

the level of lactase activity in the medium

Answer: Option C

Explanation:

No answer description available for this question.

Question: Which of the following factors will affect the sensitivity of animal cells to shear conditions?
[A].

Cell size

[B].

Availability of nutrients in the medium

[C].

The presence of shear protectorants in the medium

[D].

All of the above

Answer: Option D

Explanation:

No answer description available for this question.

Question: Animal cell cultures do not have much effect on shear forces because
[A].

the cell size is generally smaller than the critical eddy size at which shear will have an effect

[B].

cells are larger than the critical eddy size at which shear will have an effect

[C].

animal cells have cell walls

[D].

animal cells have cell membranes

Answer: Option A

Explanation:

No answer description available for this question.

Question: A stirred tank reactor containing a fluid with a density of 2.5 g.ml-1 and viscosity of 0.002 kg m-1s-1 is mixed at 120 rpm. If the fluid is mixed with an impeller having diameter 50 cm, then the Reynolds number of the liquid in the reactor is
[A].

2500

[B].

100

[C].

12,50,000

[D].

1,000,000

Answer: Option C

Explanation:

No answer description available for this question.

Question: Which pattern of mixing is preferred in stirred tank reactors during the culture of aerobic microorganisms?
[A].

Laminar flow

[B].

Transient flow

[C].

turbulent flow

[D].

all of these

Answer: Option C

Explanation:

No answer description available for this question.

Question: Mixing in stirred tank reactors can
[A].

be described as either laminar, transient or turbulent

[B].

achieve turbulent conditions by increasing the stirrer speed

[C].

induce laminar flow conditions by the addition of baffles

[D].

all of the above

Answer: Option A

Explanation:

No answer description available for this question.