Biology

Microorganisms in Food Production

1,120 Questions

Microorganisms play a vital role in food production through processes like fermentation and bioprocessing. Questions on this topic cover the use of yeast, bacteria, and industrial microbiology. These concepts are important for science sections in various competitive exams.

Alcoholic fermentationDairy beverage productionIndustrial ethanol preparationCitric acid productionBiodigester temperature

Microorganisms in Food Production Questions

Multiple choice biology chemical coordination in plants ethylene plant hormones plants and animal hormones

Ethylene is involved  in .........................

  1. Aerobic respiration

  2. Anaerobic respiration

  3. Climacteric respiration

  4. Fermentation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ethylene is an important natural plant hormone, used in agriculture to force the ripening of fruits. Binding of ethylene to the receptors unleashes a signaling cascade that leads to activation of transcription factors and the turning on of gene expression. The climacteric is a stage of fruit ripening associated with increased ethylene production and a rise in cellular respiration.

Multiple choice biology chemical coordination in plants ethylene plant hormones plants and animal hormones

Ethylene is connected with

  1. Aerobic respiration

  2. Climacteric respiration

  3. Anaerobic respiration

  4. Fermentation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ethylene is a plant hormone. It is also called as ripening hormone as it is responsible for ripening of fruits. Fruit ripening is accompanied by increase rate of respiration. The climacteric respiration occurs during fruit ripening which is associated with increased ethylene production. Due to increased respiration, complex carbohydrates are broken down into simpler sugars and cell wall becomes soft. 

Thus, the correct answer is option B.

Multiple choice zoology respiratory system do plants breathe? plant respiration respiration-plants

When yeast and sugar solution are left to stand without oxygen for some time they develop a characteristic smell due to the production of new compound, which is

  1. Ethanol

  2. Ammonia

  3. Carbondioxide

  4. Sodium carbonate
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
When yeast has both sugar and oxygen available to it, it undergoes aerobic respiration to produce energy, water and carbon dioxide. In the absence of oxygen, yeast switches over to a process called anaerobic respiration. During which, sugar is fermented to produce energy, carbon dioxide, and ethanol. Yeast that produces ethanol from the sugar has a characteristic smell and this process is generally used to ferment wine.
So, the correct answer is 'Ethanol'.
Multiple choice zoology respiratory system do plants breathe? plant respiration respiration-plants

The product obtained in the anaerobic respiration of yeast is 

  1. Lactic acid

  2. Pyruvic acid

  3. Ethanol

  4. Acetic acid
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The following reaction is of anaerobic respiration in yeast-      
                     zymase
 C₆H₁₂O₆  -------------------->  C₂H₅OH + 2CO₂  +  50KJ energy
                        yeast

Here, the ethanol is a by-product of anaerobic respiration. It takes place in the cytoplasm of the cell.

Multiple choice zoology respiratory system do plants breathe? plant respiration respiration-plants

Which one is product of aerobic respiration?

  1. Malic acid

  2. Ethyl alcohol

  3. Lactic acid

  4. Pyruvic acid.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Glucose breakdown into pyruvic acid in the absence of oxygen and in the absence of oxygen pyruvic acid is converted into lactic acid even yeast in converted to ethyl alcohol in no-oxygen.

So the correct option is 'Malic acid'.

Multiple choice zoology respiratory system do plants breathe? plant respiration respiration-plants

Which can readily respire without oxygen?

  1. Anabaena

  2. Saccharomyces

  3. Mushroom

  4. Fish
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Yeast possesses good fermentation potential in the absence of oxygen. Saccharomyces grow anaerobically (without oxygen) same as it grows in aerobically (with oxygen).

So the correct option is 'Saccharomyces'.

Multiple choice zoology respiratory system do plants breathe? plant respiration respiration-plants

The respiratory process of yeast is

  1. Rarely anaerobic

  2. Anaerobic

  3. Purely aerobic

  4. Both aerobic and anaerobic
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A unicellular organism like yeast can carry out both aerobic as well as anaerobic respiration depending on the environmental conditions. Anaerobic respiration is usually alcoholic fermentation and the end products are ethanol and carbon dioxide. Aerobic respiration produces CO$ _2$ and H$ _2$O as end products.

So, the correct answer is 'Both aerobic and anaerobic'.

Multiple choice biology improvement in food resources crop variety improvement improvement if crop varieties improvement in crop variety

What makes the bread soft and fluffy?

  1. Finely ground flour

  2. Alcohol given off during fermentation of sugar

  3. Carbon dioxide gas given off during fermentation of sugar

  4. Oxygen gas
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Yeast ferments the sugar present in the dough into carbon dioxide. The ${ CO } _{ 2 }$ released from the yeast fills the dough and increases its volume. Once, the bread has baked, the heat causes the bubbles to break and makes the bread light and fluffy.

Multiple choice apical dominance auxins and gibberellins growth and development plant growth and development biology

Select the correct one.

  1. Beer produced by distillation of fermented broth

  2. Bottled juices are cleared by protease and pectinase

  3. Methanogens digest cellulose aerobically

  4. Streptokinase is used to lower the blood cholesterol
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Protease and pectinase are enzymes used in the food industry to clarify fruit juices by breaking down cell wall components. Beer is produced by fermentation, not distillation; methanogens are anaerobic; streptokinase is a clot buster, not a cholesterol-lowering agent.

Multiple choice commercial studies biotechnology: general introduction introduction to genetic engineering and production of insulin use of efficient and eco-friendly technology genetics of the future

The typical machine for production of bioproducts through microbia is

  1. Sterilized glassware

  2. Microprojectile

  3. Autoclave

  4. Fermenter
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Fermenter is an apparatus that maintains optimal conditions for the growth of microorganisms, used in large-scale fermentation and in the commercial production of antibiotics and hormones. 

Therefore, the correct answer is option D.

Multiple choice biology cell biology cell as structural and functional unit introduction to cell biology cell : the basis of life

New cells generate from

  1. Bacterial fermentation.

  2. Regeneration of old cells.

  3. Pre-existing cells.

  4. Abiotic material.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
New cells generate from pre-existing cells. Rudolf Virchow (1985) first explained that cells divide and new cells are formed from pre-existing cells (omnis cellula-e cellula). He modified the hypothesis of Schleiden and Schwann to give cell theory a final shape.
Cell theory now is understood as:
All living organisms are composed of cells and the product of cells.
All cells arise from pre-existing cells.
Multiple choice biology cell biology cell as structural and functional unit introduction to cell biology cell : the basis of life

New cells generate from :

  1. Bacterial fermentation

  2. Regeneration of old cells

  3. Pre-existing cells

  4. Abiotic materials
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

New cells generate from pre-existing cells. Rudolf Virchow (1985) first explained that cells divide and new cells are formed from pre-existing cells (omnis cellula-e cellula). He modified the hypothesis of Schleiden and Schwann to give cell theory a final shape.
Cell theory now is understood as:

  1. All living organisms are composed of cells and the product of cells.
  2. All cells arise from pre-existing cells.

    Multiple choice biology introduction to microbiology commercial use of microorganism microbes in household and industry food production and microorganisms

    Which of the following microorganisms converts milk into curd ?

    1. Yeast

    2. Aspergillus

    3. Penicillium

    4. Bacteria
    Reveal answer Fill a bubble to check yourself
    D Correct answer
    Explanation

    Lactobacillus converts milk into curd. It acts on the lactose of the milk and turns it into lactic acid. The increased acidity leads to the coagulation of casein protein of the milk and turns it into curd.

    So, the correct answer is option D.

    Multiple choice biology introduction to microbiology commercial use of microorganism microbes in household and industry food production and microorganisms

    Which of the following is the microbe used in manufacturing vinegar?

    1. Streptococcus thermophilus

    2. Saccharomyces cerevisiae

    3. Acetobacter

    4. Aspergillus oryzae
    Reveal answer Fill a bubble to check yourself
    C Correct answer
    Explanation

    The bacteria Acetobacter aceti is involved in the conversion of ethanol formed during fermentation into vinegar. This can happen when Acetobacter bacteria acts on alcoholic beverages such as wine and, therefore, vinegar may also be an undesirable product formed during alcoholic beverage production.