Fermentation Process MCQ

Fermentation is a biological process that takes place in an anaerobic environment. The initial step in fermentation is the same as it is in cellular respiration: the formation of pyruvic acid by glycolysis, which produces net 2 ATP molecules. Pyruvate is then converted to lactic acid, ethanol, or other compounds in the next phase. NAD+ is generated here, and it is re-used in the glycolysis process.

Q1. Which of the following is produced using Monascus purpureus:

1. Statins

2. Citric acid

3. Ethanol

4. Streptokinase

Ans. The correct answer is option ‘1’ statins.

Q2. Which of the following type of fermentation is observed in yeasts 

1. Acrylic fermentation

2. Alcoholic fermentation

3. Lactic acid fermentation

4. Pyruvic fermentation

Ans. Correct option is ‘2’ alcoholic fermentation. 

Q3. Which of the following is the final electron acceptor of the lactic acid fermentation:

1. Lactic acid

2. Oxygen

3. Pyruvate

4. NAD

Ans. Correct option is ‘3’ pyruvate.

Q4. Which product is not formed during fermentation

1. Lactate

2. Carbon dioxide

3. Ethanol

4. Oxygen

Ans. The correct option is ‘4’ oxygen. 

Q5. Which among the following is not a vegetable or fruit-based fermented product?

1. Vinegar

2. Wine

3. Sauerkraut

4. Beer

Ans. Here the correct answer is option ‘1’ vinegar.

Q6. Which if the following is one of the most commonly used fermented cereal 

1. Wheat

2. Rice

3. Bread

4. Yoghurt

Ans. Here the correct answer is option ‘3’ bread.

Q7. Glucose molecule during the process of glycolysis is broken down into which of the following:

1. Four pyruvic acid

2. Two pyruvic acid

3. Three pyruvic acid

4. One pyruvic acid

Ans. The correct answer is option ‘2’ two pyruvic acids.

Q8. Fermentation process takes place in the

1. Presence of oxygen

2. presence of nitrogen

3. Presence of carbon

4. Absence of oxygen

Ans. Correct answer is option ‘4’ in the absence of oxygen.

Q9. The least yield of ATP is observed can be observed in which of the following:

1. Fermentation

2. Aerobic respiration

3. Anaerobic respiration

4. Same in (a), (b), and (c)

Ans. The correct answer is option ‘1’ fermentation.

Q10. Anaerobic respiration by yeast results in the production of

1. Wine and Beer

2. CO2

3. Alcohol

4. All of the above

Ans. Here, the correct option is ‘4’ all of the above.

Q11. Single cell protein (SCP) refers to the production of ?

1. Extracellular proteins

2. Metabolites

3. Intracellular proteins extraction

4. Fermentation of waste products

Ans. The correct option is ‘4’ fermentation of waste products. Single-cell proteins develop when microbes ferment waste materials (including wood, straw, cannery, and food-processing wastes, residues from alcohol production, hydrocarbons, or human and animal excreta). Single-cell protein (SCP) is known to be an edible unicellular microorganism. The biomass or protein extracted from pure or mixed cultures of algae, yeasts, fungi or bacteria might have been used as an ingredient or a substitute for protein-rich foods, and is suitable for human consumption or as animal feed.

Q12. Which among the following do not possess the property of production of secondary metabolites?

1. Filamentous fungi

2. Filamentous bacteria

3. Enterobacteria

4. Sporing bacteria

Ans. The correct answer is option ‘3’. Not every microorganism is able to undergo secondary metabolism – it is common amongst the filamentous bacteria and fungi and the sporing bacteria but it is not found, for example, in the Enterobacteriaceae. Hence, the taxonomic distribution of secondary metabolism is very different from that of primary metabolism.

Q13. State whether secondary metabolites are useful?

1. True

2. False

Ans. The correct answer is option ‘1’ true. As many secondary metabolites possess antimicrobial activity, while others are specific enzyme inhibitors, some are growth promoters and many have pharmacological properties. Hence, the products of secondary metabolism have formed the basis of a number of fermentation processes.

Q14. Which among the following is referred to as an upstream process?

1. Media formulation

2. Product purification

3. Product recovery

4. Cell lysis

Ans. The correct answer is option ‘1’ media formulation. Upstream processing involves formulation of the fermentation medium, sterilisation of air, fermentation medium and the fermenter, inoculum preparation and inoculation of the medium.

Q15. Which of the following is a downstream process?

1. Screening

2. Product recovery

3. Media formulation

4. Sterilization of media

Ans. The correct answer is option ‘2’ product recovery. Downstream Processing involves the recovery of the products in a pure state and the effluent treatment. Product recovery can be carried out via a series of operations involving cell separation by settling, centrifugation or filtration; product recovery by disruption of cells (if the product is produced intracellularly); extraction and purification of the product. Finally, the effluents are treated by chemical, physical or biological methods.

Q16. Alcoholic fermentation is carried out by which of the following yeast

1. Lactobacillus

2. Escherichia coli

3. Bacillus

4. Saccharomyces cerevisiae

Ans. Here, the correct answer is option ‘4’ Saccharomyces cerevisiae. It is a species of yeast. It has been instrumental to winemaking, baking, and brewing since ancient times. It is thought to have been originally isolated from the skin of grapes (one can see the yeast as a component of the thin white film on the skins of some dark-coloured fruits such as plums; it exists among the waxes of the cuticle)

Q17. Which among the following is not a probiotic?

1. Escherichia coli

2. Saccharomyces cerevisiae

3. Fungi

4. Lactobacillus

Ans. The correct answer is option ‘3’ fungi. Probiotics refers to live bacteria and yeasts that are good for one’s health, mainly the  digestive system. Example – Lactobacillus species (L. acidophilus, L. casei, L. reuteri, L. bulgaricus, L. plantarum, L. johnsonii, and L. lactis), Bifidobacterium species (B. bifidum, B. longum, B. breve, B. infantis, B. lactis, and B. adolescentis), and different other microbes such as Bacillus cereus, Escherichia coli, Non pathogenic, Streptococcus thermophilus, Enterococcus faecalis, and Saccharomyces cerevisiae

Q18. State whether  biofuels are products of fermentation

1. True

2. False

Ans. The correct answer is option ‘1’ true.  Study and development of cell factories for production of biofuels (bioethanol, biobutanol, biodiesel) and biochemicals (3-hydroxypropionic acid and ethylene). A common challenge faced by these cell factories is the need for high yield and productivity in order to make the potential production cost effective and competitive with petroleum based production. An efficient cell factory requires many rounds of metabolic engineering as well as a carefully designed and optimized fermentation process. Saccharomyces cerevisiae, is commonly used.