Question

Which of the following statement(s) is/are correct?
(i) Pyruvate can be converted into ethanol and carbon dioxide by yeast
(ii) Fermentation takes place in aerobic bacteria
(iii) Fermentation takes place in mitochondria
(iv) Fermentation is a form of anaerobic respiration

• A. (i) and (iii)
• B. (ii) and (iv)
• C. (i) and (iv)
• D. (ii) and (iii)

Answer 1

The correct option is C

(i) and (iv)

The correct option is C.

Explanation for the correct option:

Statement (i):

1. Pyruvate, the byproduct of glycolysis, is eventually destined for transport into mitochondria as a master fuel input supporting citric acid cycle carbon flux.
2. Pyruvate is produced from numerous sources in the cellular cytoplasm.
3. Pyruvate can be fermented by yeast to produce ethanol and carbon dioxide.
4. Anaerobic respiration is the name given to this process since it occurs without the presence of air (oxygen).
5. The cytoplasm is where it happens. In the mitochondria, pyruvate is broken down using oxygen, or aerobic respiration.

Statement (iv):

1. Fermentation is an anaerobic chemical process that breaks down molecules like glucose.
2. When an athlete exercises too hard, not enough oxygen is delivered to the muscles, resulting in anaerobic respiration.
3. As a result, lactic acid is created as a byproduct of the glucose reaction.
4. Cellular respiration, known as anaerobic respiration, occurs when there is no oxygen present.
5. Anaerobic pathways, like fermentation, are prevalent in most prokaryotes and unicellular eukaryotes.
6. Acids and alcohol are produced when glucose is partially oxidized in this process.

Explanations for the incorrect options:

Statement (i):

1. A chemical reaction known as fermentation breaks down molecules like glucose.
2. As they work to mitigate the deleterious effects of the reactive oxygen species produced as a result of the presence of molecular oxygen, these three enzymes are crucial for the aerobic biology of aerobes.
3. Fermentation is a form of anaerobic respiration.

Statement (ii):

1. Aerobic respiration takes place in mitochondria, while fermentation occurs in the cytoplasm of bacteria that respire anaerobically.

Final answer: The correct statements are (i) and (iv).