Question

Refer the figure showing major pathway of anaerobic respiration.


Identify P, Q, R and S in the above.

• A. $P-NA{D}^{+}\text{;Q-Ethanol; R-Lactic acid; S-PEP}$
• B. ${\text{P-Ethanol; Q-NAD}}^{+};\text{R-Lactic acid; S-ATP}$
• C. $P\text{-Lactic acid; Q-Ethanol; R-Glucose; S-ADP}$
• D. $\text{P-NAD; P-Lactic acid; R-Ethanol; S-DHAP}$

Answer 1

The correct option is A $P-NA{D}^{+}\text{;Q-Ethanol; R-Lactic acid; S-PEP}$

$P-NA{D}^{+}\text{;Q-Ethanol; R-Lactic acid; S-PEP}$

Pyruvic acid is the final product of glycolysis. Glycolysis produces 2 ATP, 2 NADH, and 2 pyruvate molecules. Glycolysis, or the aerobic catabolic breakdown of glucose, produces energy in the form of ATP, NADH, and pyruvate, which itself enters the citric acid cycle to produce more energy.

Bacteria produces lactic acid via fermentation. Anaerobic respiration occurs in muscles during exercise due to insufficient availability of oxygen. Aerobic respiration requires more energy than anaerobic respiration because in anaerobic respiration glucose is incompletely broken down. Due to incomplete breakdown, lactic acid is produced instead of carbon dioxide and water later.

Ethyl alcohol is produced as a result of fermentation in yeast, along with that, CO${}_2$​ is released as a by-product.