Tag: cell respiration

Questions Related to cell respiration

RQ in anaerobic respiration is?

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

  1. $0.7$

  2. $0.9$

  3. Unity

  4. Infinity

Show answer
Correct Option: D
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'.

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

  1. Extinguishes the flame

  2. Bursts into flame when ignited

  3. Turns lime water milky

  4. Both (a) and (c)

Show answer
Correct Option: D
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).

Alcoholic fermentation is carried out by

biology respiration in plants fermentation cell respiration living organisms and energy production

  1. Saccharomyces.

  2. Lactobacillus.

  3. Clostridium.

  4. Aspergillus.

Show answer
Correct Option: A
Explanation:

Saccharomyces is used in fermentation is alcohol. Saccharomyces will be grown in anaerobic conditions same as growth takes place in aerobic conditions.

So the correct option is 'Saccharomyces.'

Formation of lactic acid from pyruvate requires

biology respiration in plants fermentation cell respiration living organisms and energy production

  1. Decarboxylation

  2. Reduction

  3. Oxidation

  4. Hydration

Show answer
Correct Option: B
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. 

Alcoholic fermentation occurs in the presence of

biology respiration in plants fermentation cell respiration living organisms and energy production

  1. Zymase.

  2. Amylase.

  3. Invertase.

  4. Maltase.

Show answer
Correct Option: A
Explanation:

The fermentation process is catalyzed by enzyme Zymase which converts sugar to ethanol and carbon dioxide.

So the correct option is 'Zymase.'

Alcoholic fermentation uses

biology respiration in plants fermentation cell respiration living organisms and energy production

  1. Ribosomes

  2. Golgi bodies

  3. Mitochondrial enzymes

  4. Cytoplasmic enzymes

Show answer
Correct Option: D
Explanation:

The production of ethanol is called alcohol fermentation. The very first reaction catalyzed by a cytoplasmic enzyme, pyruvate decarboxylase.

So the correct option is 'Cytoplasmic enzymes.'

Which enzyme converts glucose into alcohol?

biology respiration in plants fermentation cell respiration living organisms and energy production

  1. Invertase

  2. Lipase

  3. Zymase

  4. Diastase

Show answer
Correct Option: C
Explanation:

Fermentation process is catalyzed by enzyme Zymase which converts sugar to ethanol and carbon dioxide.

So the correct option is 'Zymase.'

Anaerobic respiration following glycolysis is

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

  1. Oxidative phosphorylation

  2. Krebs cycle

  3. Fermentation

  4. Both A and B

Show answer
Correct Option: C
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'.

Which of the following is correct about fermentation?

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

  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

Show answer
Correct Option: B
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 $CO _2$'  

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

  1. (i),(ii) and (iii)

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

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

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

Show answer
Correct Option: D
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)'.