Question

In the anaerobic reaction of muscle, lactic acid is produced which causes painful tiredness. Where and by which mechanism lactic acid is catabolized?
A. In muscle by monokinase action
B. In muscle by Lohmans action
C. In liver by Cori cycle
D. In liver by phosphagen reaction

Answer 1

Hint: During anaerobic reaction in muscle cells, the lactate is produced through anaerobic glycolysis. Because it is anaerobic, there is no oxygen being used during respiration. Where the sugar is used to create ‘Adenosine triphosphate’ (ATP) and there first the lactate is produced which is then converted to lactic acid.

Complete answer:
1. As we have discussed about the lactic acid being formed in muscular cells, they then are transferred to the liver.
2. Inside the liver, the lactic acid is taken which is then converted to Pyruvate which is again converted to Glucose.
3. The Glucose again is transported to Muscle cells so that during exercise, the glucose can be used by the muscle cells for each and every second.
4. Most importantly, the glucose is converted to Pyruvate in muscle cells but along with those Pyruvates, the lactic acid is also produced.
5. Which is why, the assistance of the liver is necessary in order to retain the cycle active.
6. This cycle is named after two great discoverers, Carl Ferdinand Cori and Gerty Cori, who invented the entire process by 1947.
 So, the right answer is:- It is a Cori cycle as being performed in the liver.

Hence the correct answer is option ‘C’.

Additional Information:Along with anaerobic respiration, the aerobic respiration also took place in muscular cells. But during intensive workouts, as more power or energy is needed, so the muscular cells also do anaerobic respirations.

Note: We should understand why glucose is required by muscles first. Muscles during intensive workouts, every time requires energy which is provided through Adenosine triphosphate (ATP). In order to get this, lactic acid is collected in the muscles.