Tag: fermentation

Questions Related to fermentation

Multiple choice biology life processes in living organisms- part 1 fermentation cell respiration living organisms and energy production

RQ in anaerobic respiration is?

  1. $0.7$
  2. $0.9$
  3. Unity

  4. Infinity

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

During aerobic respiration, oxygen is consumed and carbon dioxide is released. The ratio of the volume of carbon dioxide given out to the volume of oxygen absorbed in respiration, i.e., CO$ _2$/O$ _2$ is called respiratory quotient (RQ) or respiratory ratio.  in anaerobic respiration, CO2 is evolved but O2 is not consumed, and therefore RQ is infinite (∞).

Equation is as follows:                                               
                            C$ _6$H$ _12$O$ _6$ $\rightarrow$ 2C$ _2$H$ _5$OH + 2CO$ _2$ + energy
RQ CO$ _2$/O$ _2$ = 2/0 = infinity

So the correct option is 'infinity'.

Multiple choice biology respiration in plants fermentation cell respiration living organisms and energy production
A test tube containing molasses solution and yeast is kept in a warm place overnight. The gas collected from this mixture
  1. Extinguishes the flame

  2. Bursts into flame when ignited

  3. Turns lime water milky

  4. Both (a) and (c)

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Yeast do anaerobic fermentation by consuming sugar and forming ethanol and $CO _2$.  As Molasses mainly contain sugar, yeast will do anaerobic fermentation of the molasses and forms $CO _2$ gas as a by-product. 
This $CO _2$ gas can (i) extinguishes the flame, and (ii) Turns lime water milky.
So, the correct answer is (D).
Multiple choice biology respiration in plants fermentation cell respiration living organisms and energy production

Formation of lactic acid from pyruvate requires

  1. Decarboxylation

  2. Reduction

  3. Oxidation

  4. Hydration

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Pyruvate + NADH $\rightarrow$ Lactic acid + NAD$^{+}$
Muscle cells convert pyruvate into lactate. Here, pyruvate (a metabolite of glucose) is reduced to lactic acid by accepting electrons from NADH, which oxidizes NADH back to NAD$^{+}$ to allow glycolysis to continue under anaerobic conditions. 

Multiple choice biology life processes in living organisms- part 1 fermentation cell respiration living organisms and energy production

Anaerobic respiration following glycolysis is

  1. Oxidative phosphorylation

  2. Krebs cycle

  3. Fermentation

  4. Both A and B

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Following glycolysis, if the oxygen is available, end products of glycolysis directly enter Krebs' cycle for further oxidation and energy production. In anaerobic conditions, it chooses to get fermented and the end product is another organic substance which is incompletely oxidised, producing less energy.

So, the correct answer is 'Fermentation'.

Multiple choice biology life processes in living organisms- part 1 fermentation cell respiration living organisms and energy production

Which of the following is correct about fermentation?

  1. Bread gets fermented due to formation of lactic acid.

  2. Pulled up appearance of dough is due to production of $CO _2$
  3. Fermentation in muscles produces alcohol

  4. Both A and B

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

During the process of fermentation in the dough, the bacteria and yeast, convert carbohydrates to carbon dioxide resulting in the formation of gas bubbles. The gas bubbles expand inside the dough making it appear larger, which is called leavening. 

So the correct option is 'Pulled up appearance of dough is due to production of $CO _2$'  

Multiple choice biology life processes in living organisms- part 1 fermentation cell respiration living organisms and energy production
Which of the following describes the significance of fermentation?
(i) Production of alcohol in the brewing industry
(ii) Making of dough in the baking industry
(iii) Curing of tea and tobacco
(iv) Production of vinegar by acetic acid bacteria
  1. (i),(ii) and (iii)

  2. (i),(ii) and (iv)

  3. (i),(iii) and (iv)

  4. (i),(ii),(iii) and (iv)

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Alcoholic fermentation is used in the brewing industry for the production of various types of beer, whiskey and other wines. 
Carbon dioxide of alcoholic fermentation is used in the baking industry for making the bread spongy. 
Tea and tobacco leaves are curved (or removed of their bitterness) and provided with a fine flavor through fermentation. Vinegar is obtained by the fermentation activity of acetic acid bacteria.
So the correct answer is '(i),(ii),(iii) and (iv)'.