Category: Fermentation Technology Objective Questions

Fermentation Technology Multiple Choice Questions on “Media Design for Bioprocesses – Media Types”.

1. Which of the following is not a microbiological culture media?
A. Natural media
B. Synthetic media
C. Complex media
D. Semi-synthetic mediaid5fdc69f985688″

Answer: A
Clarification: The microbiological media consist of synthetic media, synthetic media, and complex media. Natural media is not the type of microbiological media. It can be solid, semi-solid or liquid in the state. It must be sterilized before any use.

2. Magnesium is required in the medium for _____________
A. Membrane stabilization
B. Production of ATP
C. Membrane structure and function
D. Amino acid synthesisid5fdc69f9856b7″

Answer: C
Clarification: Magnesium is required significantly for the role in membrane structure and function. It also acts as a cofactor for the activity of enzymes. It keeps the heartbeat steady and regulates blood glucose levels.

3. Which of the following provides the fewest problems while downstream processing?
A. Natural media
B. Synthetic media
C. Complex media
D. Semi-synthetic mediaid5fdc69f9856c7″

Answer: B
Clarification: The synthetic media provides the fewest problems while downstream processing as it is fully soluble. But it is generally used only at the small-scale level as it is very expensive and in pure form. It is used to determine the effect of a particular component on the growth of organisms.

4. Which of the following media consists of a few components which are poorly specified?
A. Natural media
B. Synthetic media
C. Complex media
D. Semi-synthetic mediaid5fdc69f9856d3″

Answer: D
Clarification: Semi-synthetic media consists of a few components whose composition is poorly specified. But a large amount of its components are of known concentration. It is required when an organism requires a substrate which is very expensive in its pure form.

5. Which of the following is responsible for the formation of foam?
A. Natural media
B. Synthetic media
C. Complex media
D. Defined mediaid5fdc69f9856de”

Answer: C
Clarification: The complex media and the semi-synthetic media is responsible for the formation of foam. This is due to the presence of amino acids, and proteinaceous material in complex media. There is a greater need of antifoams in these media types.

6. Which of the following is required for the synthesis of amino acids?
A. Phosphorus
B. Calcium
C. Magnesium
D. Sulfurid5fdc69f9856e9″

Answer: D
Clarification: Sulfur is used for the synthesis of amino acids and also for the production of vitamins e.g. biotin. It also acts as a coenzyme. The deficiency of sulfur leads to a reduction in protein synthesis. It also acts as an antibacterial agent against a few bacteria.

7. What is the composition of carbohydrates in yeast?
A. 55 %
B. 38 %
C. 32 %
D. 45 %id5fdc69f9856f3″

Answer: B
Clarification: The composition of carbohydrates in yeast is about 38%. The carbon components of yeast, bacteria, and fungi are almost similar but their nitrogen concentration varies largely. This is the way in which different organisms grow.

8. What is the use of calcium in media?
A. Production of phospholipids
B. Production of vitamins
C. Stabilization of cell walls
D. Production of nucleic acidsid5fdc69f9856fe”

Answer: C
Clarification: Calcium is required for the stabilization of cell walls and is important particularly for the formation of endospore as it contains a high concentration of calcium dipicolinate.

9. Which of the following is used for the production of nucleic acids?
A. Phosphorus
B. Calcium
C. Magnesium
D. Sulfurid5fdc69f985708″

Answer: A
Clarification: Phosphorus is used for the production of nucleic acids. It is also used in the production of phospholipids, and generation of energy in the form of ATP and ADP. It is also required for growth and repair of body cells and tissues.

10. There is a high amount of nutrients in growth media.
A. True
B. Falseid5fdc69f985712″

Answer: B
Clarification: There is a high amount of nutrients in the fermentation media and is used in creating final products. Whereas, low amount of nutrients are present in the growth media. As for example, yeast requires 1 % carbon for normal growth and about 13 % of carbon during fermentation.

11. Which of the following media is used in determining the colony characteristics of the isolate?
A. Solid media
B. Semi-solid media
C. Liquid media
D. Complex mediaid5fdc69f98571c”

Answer: A
Clarification: Solid media is useful in determining the colony characteristics of the isolate. It is also used in the isolation of bacteria. It usually contains an agar medium at a concentration of about 2%, which is a solidifying agent.

12. Which of the following is not an example of selective media?
A. Mannitol Salt Agar
B. MacConkey’s agar
C. Crystal Violet Blood Agar
D. Tryptic Soyid5fdc69f985726″

Answer: D
Clarification: Tryptic Soy is an example of broth which is used in broth formula. Mannitol agar, MacConkey’s agar, crystal violet blood agar, Thayer Martin agar, etc. are examples of selective media.

13. Which of the following primary metabolite is produced by Streptomyces erythreus?
A. Penicillin
B. Cephalosporin
C. Gibberellin
D. Erythromycinid5fdc69f985731″

Answer: D
Clarification: The primary metabolite is produced by Streptomyces erythreus is Erythromycin. It is used in the production of antibiotic which is useful in the treatment of a variety of bacterial infections and many respiratory tract infections like bronchitis, pneumonia, etc.

14. Xanthum gum is ____________
A. A rheology modifier
B. A vitamin
C. A flavor enhancer
D. An alcoholic beverageid5fdc69f98574b”

Answer: A
Clarification: Xanthum gum is used as a rheology modifier and food additive. It is produced by Xanthonomonas campestris as a primary metabolite. It is a polysaccharide which is also used as a stabilizer.

15. Crude media contains inorganic salts with a carbon source.
A. True
B. Falseid5fdc69f985756″

Answer: A
Clarification: Crude media contains inorganic salts containing cations and anion along with a carbon source. Some of the ions such as magnesium ions, phosphates or sulfates are required by microorganisms which are fulfilled by the addition of these ions to balance the crude media.

Fermentation Technology Questions and Answers for Entrance exams on “Properties of Fermentation Vessels”.

1. Which of the following is a fabricated material used for the construction of a fermentation vessel?
A. Wood
B. Ceramics
C. Stone
D. Gourdsid5fdba55f8be92″

Answer: B
Clarification: Ceramic is a fabricated material used for the construction of fermentation vessels. It is inert, non-porous, inexpensive and suitable for small scale domestic brewing. Wood, stone, gourds are natural materials used for constructing fermentation vessel.

2. Which of the following has a very high thermal conductivity?
A. Concrete
B. Glass
C. Wood
D. Copperid5fdba55f8bec3″

Answer: D
Clarification: Copper has a very high thermal conductivity which is used as a fabricated material in the construction of fermentation vessel. It is strong, durable, expensive, easily worked, and cleaned. Glass, concrete, and wood have very low conductivity.

3. Which of the following is not used in the construction of a fermentation vessel?
A. Iron
B. Steel
C. Potassium
D. Stainless steelid5fdba55f8bede”

Answer: C
Clarification: Potassium cannot be used in the construction of a fermentation vessel. Iron, steel and stainless steel can be used for constructing a fermentation vessel. They are porous, durable, strong, and has a high thermal conductivity.

4. Which of the following is a natural material used in the fermentation vessel construction?
A. Aluminium
B. Glass
C. Plastic
D. Slateid5fdba55f8bef4″

Answer: D
Clarification: Slate is a natural material used in the construction of the fermentation vessel. It is durable, non-porous, inert, very heavy and has low thermal conductivity. It is suitable for small vessel and rectangular vessels.

5. The composition of chromium in ferritinic alloy is _____________
A. 13 – 20 %
B. 10 – 12 %
C. 18 – 20 %
D. 25 – 30 %id5fdba55f8bf09″

Answer: A
Clarification: The composition of chromium in Ferritinic alloy is 13 – 20 % with less than 0.1% carbon content. They are usually less expensive. They also have good resistance to stress-corrosion cracking.

6. Which of the following alloy has up to 2% nickel content?
A. Ferritinic
B. Austenitic Type 304
C. Martensitic
D. Austenitic Type 316id5fdba55f8bf1f”

Answer: C
Clarification: Martensitic alloy has nickel content of up to 2% with 10 – 12 % of chromium and 0.2 – 0.4% carbon content. Austenitic alloys have more than 10% of carbon content and ferritinic alloys have little or no nickel content.

7. The 4 x 400 hl vessels is better than 1 x 1600 hl vessel in terms of _____________
A. Flexibility
B. Vessel space utilization
C. Capital costs
D. Revenue costsid5fdba55f8bf33″

Answer: A
Clarification: The 4 x 400 hl vessel is better than 1 x 1600 hl vessel in terms of flexibility. It is good that the system has the ability to ferment four simultaneous product lines whereas in 1 x 1600 hl vessel only one product line can be fermented at a time.

8. Which of the following is not important for the maintenance of the hygiene of vessel?
A. The vessels must be capable of being cleaned
B. Before using, it must be acted upon by antibiotics
C. The vessel should be disinfected prior to filling wort
D. The vessel must present a barrier to the external environmentid5fdba55f8bf48″

Answer: B
Clarification: The hygiene requirements are: The vessels must be capable of being cleaned between fermentations, It must be necessary to disinfect the vessel prior to filling the wort, and during fermentation, the vessel must be present as a barrier to the external environment. Using antibiotics is not required.

9. Which of the following is not an element in controlling and monitoring brewery fermentations?
A. Set of final conditions
B. Set of initial conditions
C. Controlling fermentation rate
D. Monitoring the progress of fermentationid5fdba55f8bf5c”

Answer: A
Clarification: There are mainly the elements of controlling and monitoring brewery fermentations. They are Setting of the desired initial conditions, Monitoring the progress of fermentation and Controlling the rate, and identifications of completion of key stages during fermentation.

10. The carbon dioxide concentration can be monitored by ____________
A. Manual monitor
B. Automatic monitor
C. Alarm
D. Automatic monitor with an audible alarmid5fdba55f8bf6e”

Answer: D
Clarification: The carbon dioxide concentration in the fermenting room can be monitored at all times using an automatic monitor fitted with an audible alarm. It is necessary to provide ventilation in the fermentation room so that gases are dissipated safely.

11. Which of the following is referred to as machinery mould?
A. Geotrichum candidum
B. Geotrichum capitatum
C. Geotrichum pneumonia
D. Geotrichum klebahniiid5fdba55f8bf81″

Answer: A
Clarification: Geotrichum candidum is also referred to as machinery mould. It is because it is capable of producing slimy growth on the surface of the metals. It is also called as the black mould.

12. Who reported that height-aspect-ratio is linked with perturbations in beer flavour?
A. Hoggan
B. Shardlow
C. Vrieling
D. Ulenbergid5fdba55f8bfab”

Answer: C
Clarification: Vrieling in 1978 reported that height-aspect-ratio is linked with perturbations in beer flavour. The concentrations of the important flavour compounds, ethyl acetate and isoamyl acetate, formed during fermentation is inversely related to the height of the vessel.

13. The wood used in the vessel is relatively light.
A. True
B. Falseid5fdba55f8bfc3″

Answer: A
Clarification: The wood used in the fermentation vessel is relatively lighter. It should be durable, easily worked and shaped and requires inert lining. It should be of low thermal conductivity and must be well-seasoned.

14. Stainless steel is expensive.
A. True
B. Falseid5fdba55f8bfd6″

Answer: A
Clarification: Stainless steels are very expensive than carbon steel because it contains a variety of alloying elements like nickel, chromium, manganese, etc. There are different grades of stainless steel available according to the price range.

To practice all areas of Fermentation Technology for Entrance exams, .

Fermentation Technology Multiple Choice Questions on “Microbial Growth Kinetics – Continuous Culture”.

1. The Continuous culture is a/an ______ culture system.
A. Open
B. Closed
C. Isolated
D. Semi-closedid5fdbc659c84f8″

Answer: A
Clarification: The Continuous culture is an open culture system where the nutrients are added in a continuous fashion. The batch culture is a closed system with limiting the number of nutrients and fed-batch culture is a semi-closed system.

2. During continuous culture/fermentation, nutrients in the fermenter are utilized at a fast rate.
A. True
B. Falseid5fdbc659c8526″

Answer: A
Clarification: In Continuous Fermentation, the nutrients in the fermenter are added continuously and are utilized by microbes at a fast rate whereas, in batch culture, the nutrients are utilized at a slow rate.

3. Which Growth phase is usually longer in continuous culture?
A. Log
B. Exponential
C. Stationary
D. Deathid5fdbc659c8534″

Answer: B
Clarification: Exponential phase is usually longer as the nutrients are added continuously and therefore the microbes show exponential growth. This is the phase of the maximum growth rate where the growth of cells usually increases.

4. What is the dilution rate (D.?
A. D = F/V
B. D = V/F
C. D = µF
D. D = µDid5fdbc659c853f”

Answer: A
Clarification: The flow of medium into the vessel is called dilution rate, and is defined as,
D = F/V
where V is volume and F is the flow rate.

5. What is the unit of flow rate (F)?
A. dm³ h^-1
B. km³ h^-1
C. ml³ h^-2
D. dm² h^-2id5fdbc659c8548″

Answer: A
Clarification: Flow rate is the product of dilution rate and volume of the vessel. The unit of dilution rate is h^-1 and that of the volume of the vessel is dm³. Therefore, the unit of flow rate is dm³ h^-1.

6. The chemostat and turbidostat are the types of bioreactors that are used in which of the following culture?
A. Batch culture
B. Continuous culture
C. Fed-Batch culture
D. Solid State cultureid5fdbc659c8551″

Answer: B
Clarification: Turbidostat is a microbiological culture device, similar to a chemostat, which has feedback between the turbidity of the culture vessel and the dilution rate. Continuous fermentation is useful in the production of potentially more important products than batch fermentation.

7. Which scientist(s) gave a full kinetic description of external and internal feedback system?
A. Monod
B. Pirt
C. Bull
D. Harte and Webbid5fdbc659c855a”

Answer: B
Clarification: Pirt in 1975 gave a full description of these feedback systems and he also discussed the kinetics of product of microbial culture.

8. A multistage system is shown below. Label the stages 1 and 2.

A. 1-Medium inlet and 2-culture effluent
B. 1-Mixing chamber and 2-culture effluent
C. 1-Medium inlet and 2-Liquid reservoir
D. 1-Culture effluent and 1-Medium Inletid5fdbc659c8563″

Answer: A
Clarification: Multistage system is a chemostat that is separated in different stages where the medium inlet is followed by culture effluent which is followed by effluent collection or subsequent stages.

9. What are the disadvantages of continuous culture?
A. It can rarely be used for other productions
B. The growth rate is higher
C. If contamination occurs, huge volumes of the product may be lost
D. It is very useful for processes involving the production of primary metabolitesid5fdbc659c856c”

Answer: C
Clarification: Continuous culture is an open culture system and therefore, there are very high chances of microbial contamination. Thus, a huge amount of product may be lost. The other three options include the advantages of continuous culture.

10. In continuous culture, the turnover rate is high.
A. True
B. Falseid5fdbc659c8574″

Answer: A
Clarification: The turnover rate in continuous culture is higher because the nutrients are added constantly and continuously and thus the products are produced in a high amount.

11. Which of the following is not the type of continuous brewing?
A. Cascade system
B. Multistage system
C. Tower system
D. Extract brewingid5fdbc659c8588″

Answer: D
Clarification: The main types of continuous brewing are cascade, multisystem and the tower system. The extract brewing is a type of home brewing. The continuous brewing is useful in converting the wort into beer.

12. All the constituents of medium are excess in _______
A. Chemostat
B. Turbidostat
C. Batch culture
D. Fed-Batch cultureid5fdbc659c8591″

Answer: A
Clarification: In the continuous culture all the constituents of the medium are in excess in the chemostat. The batch and the fed-batch culture contains a limited amount of nutrients in the medium.

13. Which carbon source has great application for SCP production?
A. Cellulose
B. Starch
C. Methanol
D. Methaneid5fdbc659c859a”

Answer: A
Clarification: Cellulose has been investigated as a potential carbon source for SCP production and was reviewed by Callihan et al and Woodward. Cellulose is a compound present in the cell wall of plants. Humans do not have an enzyme that can digest cellulose, therefore cellulose directly gets excreted in the form of roughage.

14. The continuous culture or fermentation can be used to produce _______
A. Biomass
B. Primary metabolites
C. Secondary metabolites
D. Antibodiesid5fdbc659c85af”

Answer: B
Clarification: The continuous culture or fermentation can be used to produce primary metabolites such as amino acids, SCP, organic acids, etc. Biomass, Secondary metabolites, and a few primary metabolites are produced by batch fermentation.

15. Which of the following is NOT correct for Continuous fermentation?
A. Setup is not changed from outside once the fermentation has started
B. Nutrients are added many times
C. Closer to the natural environment
D. The small size of fermenters are requiredid5fdbc659c85b8″

Answer: A
Clarification: In Continuous Fermentation the system is open and therefore the setup can be changed from outside during the fermentation process. The other three options are possible for batch fermentation.

Fermentation Technology Multiple Choice Questions on “Other Fermentation Vessels”.

1. The operating volume of Waldhof-type fermenter is __________ for broth and air.
A. 252,000 dm³
B. 225,000 dm³
C. 215,000 dm³
D. 232,000 dm³id5fdb77458223e”

Answer: B
Clarification: The operating value of Waldhof-type fermenter is 225,000 dm³ for an emulsion of both broth and air. It was 100,000 dm³ for broth without air. The non-sterile air was introduced into the fermenter through rotating pin-wheel aerator.

2. What led to the development of Walhof-type fermenter?
A. Yeast growth
B. Bacterial growth
C. Viral growth
D. Fungi growthid5fdb774582260″

Answer: A
Clarification: The growth of yeast in sulphite waste liquor led to the development of Walhof-type fermenter. The investigations were done in Germany, Japan, and the United States of America.

3. The diameter of Waldhof-type fermenter was _______
A. 8.0 m
B. 7.8 m
C. 7.9 m
D. 8.1 mid5fdb77458226e”

Answer: C
Clarification: The diameter of Waldhof-type fermenter was 7.9 m. It was 4.3 m in height with the central tube of 1.2 m in diameter. It was made up of carbon steel, clad in stainless steel.

4. Which manufacturer developed vinegator?
A. Chemap AG
B. Solida Biotech
C. LanzaTech
D. Arzedaid5fdb77458227a”

Answer: A
Clarification: Chemap AG of Switzerland manufactured the Vinegator. Chemap solves the filtration tasks and is suited to filtration applications in which washing, drying, extraction are parts of filtration. These systems are used in Fermentation Technology, Pharmaceuticals, etc.

5. Who defined Tower Fermenter?
A. Cohee
B. Steffen
C. Ebner
D. Greenshieldsid5fdb774582285″

Answer: D
Clarification: Tower Fermenter was defined by Greenshields et al. in 1971. They described it as an elongated non-mechanically stirred fermenter with an aspect ratio of 6:1 for the tubular section or 10:1 overall.

6. The Tower fermenter was first described for _____________
A. Amylase production
B. Citric acid production
C. Cheese production
D. Beer productionid5fdb774582290″

Answer: B
Clarification: Tower fermenter was first described for citric acid production. It was in the form of glass having height: diameter ratio of 16:1 and a volume of about 3 dm³. It was the simplest type of fermenter.

7. The tower beer fermenter was patented by _________
A. Shore
B. Ulenberg
C. Owen
D. Victereroid5fdb77458229a”

Answer: A
Clarification: A vertical-tower beer fermenter was patented by Shore et al. The perforated plates were introduced in the fermenter to maximize the production of yeast.

8. Who proposed the use of cylindro-conical vessels?
A. Nathan
B. Boulton
C. Maule
D. Smithid5fdb7745822a4″

Answer: A
Clarification: The use of cylindro-conical vessels was proposed by Nathan in 1930. It was used in the brewing of lager. The operating height of vessel was 10 to 20 m and the volume of the vessel was 150,000 dm³ to 200,000 dm³.

9. Which of the following is the disadvantage of cylindro-conical vessels in brewing?
A. Time-consuming
B. Fermentation and conditioning can be carried out in the same vessel
C. Reduction in maturing time
D. Yeast separation is goodid5fdb7745822ae”

Answer: A
Clarification: The advantages of cylindro-conical vessels in brewing are: i) Reduced processing time by movement within the vessel. ii) Fermentation and conditioning are carried out in the same vessel. iii) The separation of yeast is easy and good. iv) The maturing time is reduced.

10. Which of the following is not the type of airlift fermenter?
A. Concentric Draft loop
B. Tower loop
C. ICI deep shaft
D. High pressureid5fdb7745822b8″

Answer: D
Clarification: The Airlift/Gaslift fermenters are used to reduce stress by the elimination of mechanical agitators. They are alternative to the mechanical agitated system and are mainly of 4 types: Concentric draft loop, Tower loop, ICI deep shaft, Low-pressure airlift fermenter.

11. Who developed multiple air-lift fermenters?
A. Bakker
B. Hamer
C. Reuss
D. Bayerid5fdb7745822c2″

Answer: A
Clarification: Bakker et al. in 1993 developed a multiple air-lift fermenter system in which three fermenters were incorporated into one vessel. It consists of two compartments: a central compartment and middle compartment.

12. Which of the following scientist developed the cyclone column?
A. Meyrath
B. Dawson
C. Wu
D. Hamerid5fdb7745822cb”

Answer: B
Clarification: Dawson in 1974 developed the cyclone column. It was particularly for the growth of filamentous cultures. Dawson also listed important bacteria, fungal, and yeast applications in the production of the vaccine.

13. ‘Dowpac’ is derivative of _____________
A. Polystyrene
B. Polyethene
C. Polyethylene Glycol
D. Teflonid5fdb7745822d5″

Answer: A
Clarification: The derivative of polystyrene is ‘Dowpac’. In packed towers, the column was packed with ‘Dowpac’. The packed towers are useful in the treatment of sewage and effluent.

14. Rotating-disc fermenters are used in effluent treatment.
A. True
B. Falseid5fdb7745822df”

Answer: A
Clarification: The rotating-disc fermenters are useful in the treatment of effluent. They utilize growing microbial film on rotating discs for oxidizing the effluent. The variety of fungi can be grown on the rotating discs.

15. The fermenter vessel has to pass through several tests before entering the market.
A. True
B. Falseid5fdb7745822e9″

Answer: A
Clarification: The vessel has to pass through several tests before entering the market. Those vessels which pass the tests is given a certificate by the insurance companies which then allow the vessel to be operated in the laboratory or factory.

Fermentation Technology Multiple Choice Questions on “Media Design and Preparation for Bioprocesses – Filtration”.

1. What is the pore size of the filtration membrane to remove bacteria?
A. 0.25 µm
B. 0.22 µm
C. 0.27 µm
D. 0.26 µmid5fdc811bb0f8e”

Answer: B
Clarification: The pore size of the filtration membrane to remove the bacteria is 0.22 µm. Filtration is very useful in removal for unnecessary components of the medium. The sterility of the filtration is also an important aspect.

2. The pore size for the removal of viruses is _______________
A. 20 nm
B. 30 nm
C. 25 nm
D. 35 nmid5fdc811bb0fb1″

Answer: A
Clarification: The pore size of the filtration membrane for the removal of the virus is 20 nm. The viruses are smaller than bacteria and therefore the pore size for the removal of the virus is less than that of bacteria. Viruses also reproduce inside the bacteria and can infect them which are commonly referred to as bacteriophage.

3. Which of the following is not the application of filtration?
A. Sterilization of media
B. Removal of debris
C. Plasma clarification
D. Off-gas analysisid5fdc811bb0fc0″

Answer: D
Clarification: Off-gas analysis is done with the help of mass spectroscopy and not by the filtration process. The applications of filtration are to sterilize the media, removal of debris, plasma clarification, serum clarification, endotoxin removal, cell culture clarification, additive, and buffer sterilization.

4. Which of the following filters are ideal for vitamin sterilization?
A. Bottle top filters
B. Cellulose Nitrate filters
C. Cellulose Acetate filters
D. PES membrane filtersid5fdc811bb0fcb”

Answer: A
Clarification: The bottle top filters are ideal for the sterilization of vitamins, growth factors, trace elements, buffers, etc. It is useful for sterilizing small volumes. It has a range of membranes and pore sizes which are used for suitable purposes.

5. Which of the following filter is used in the filtration of bacteria?
A. Bottle top filters
B. Oxalate filters
C. Cellulose Acetate filters
D. PES membrane filtersid5fdc811bb0fd5″

Answer: C
Clarification: Cellulose Acetate filters are used in the filtration of bacteria with a pore size of 0.22 µm. Cellulose Nitrate filters are also used for the filtration of bacteria and for sterilization of buffers and solutions.

6. The advantage of cellulose acetate filters is ________________
A. Recovery of microorganisms
B. Low throughput
C. High protein binding
D. Low flow ratesid5fdc811bb0fdf”

Answer: A
Clarification: The analytical filters along with cellulose acetate membranes are used for the recovery of microorganisms at the laboratory or industrial scale. The drawbacks of cellulose acetate filters are low throughput, high protein binding, and low flow rates.

7. Which of the following is not an advantage of PES membrane filters?
A. Low extractables
B. Fast flow
C. High protein binding
D. High throughputid5fdc811bb0fe8″

Answer: C
Clarification: The advantages of PES membrane filter have low extractables, fast flow, low protein binding, fast flow, high throughput. They are used for the sterilization of small or large volumes according to laboratory use.

8. In which of the following the size of particles retained is much smaller than the pore size of the medium?
A. Batch filtration
B. Surface filtration
C. Submerged filtration
D. Depth filtrationid5fdc811bb0ff2″

Answer: D
Clarification: In depth filtration, the size of particles retained is much smaller than the pore size of the medium. It has high capacity and the strength of filter is also higher. Examples are ceramic and sintered filters.

9. Which of the following does not influence filtration?
A. Temperature
B. Density
C. Viscosity
D. pHid5fdc811bb0ffc”

Answer: D
Clarification: The pH of the solution does not influence the filtration of the solution. The factors that affect the filtration are temperature, density, pressure, viscosity, particle size, particle shape, charge, and corrosiveness.

10. Filtration is a steady state.
A. True
B. Falseid5fdc811bb1005″

Answer: B
Clarification: The flow of liquid through a filter follows the basic rules that govern the flow of any liquid through medium offering resistance. Rate of flow is the ratio of driving force to resistance. The resistance is not constant, it increases with an increase in deposition of solids on the filter medium. Therefore, filtration is not a steady state.

11. In surface filtration, the size of particles retained is higher than the mean pore size of the medium.
A. True
B. Falseid5fdc811bb100e”

Answer: A
Clarification: The size of particles is higher than the mean pore size of the medium. It has low capacity and the particles size retained is more predictable. Examples are cellulose Acetate and Cellulose Nitrate filters.

12. The slurry is ______________
A. A suspension to be filtered
B. A porous membrane used to retain the solids
C. The solids which are present on the filter
D. A clear liquid passing through the filterid5fdc811bb1017″

Answer: A
Clarification: The slurry is a suspension that is to be filtered. It is a semi-liquid mixture which consists typically of fine particles of cement, manure, or coal suspended in water.

13. What do you mean by filter cake?
A. The cake which is to be filtered
B. A porous membrane used to retain the solids
C. The solids which are present on the filter
D. A suspension to be filteredid5fdc811bb102e”

Answer: C
Clarification: The filter cake consists of the solids which are present on the filter. It is usually the insoluble matter which is left on the filter. As the cake grows, the particulate matter is retained, resulting in the thickening of cake.

14. Which of the following process is used to separate insoluble particles from liquids?
A. Filtration
B. Extraction
C. Drying
D. Sievingid5fdc811bb1037″

Answer: A
Clarification: The filtration is the process of separation of insoluble particles from liquids. It can be physical, mechanical, biological methods are used for separation of solids from fluids. The filtrate is obtained which is collected in a glass and the residue remains on the filter.