Question

What is the example of lactic acid fermentation?

Answer 1

Hint: Fermentation is the process of breakdown of food/glucose to produce energy in the absence of oxygen or anaerobically. This process is carried out by yeast also happens in the human body. The end product of such fermentation can be alcohol or acid.

Complete answer:
The energy we require for our metabolism is obtained from the breakdown of glucose. This breakdown happens under two conditions:
 - In the presence of oxygen which takes place in the case of respiration
 - In the absence of oxygen which produces two end products lactic acid(insufficient oxygen) or ethanol which is produced by the Yeast.

Let us discuss lactic acid fermentation:
Lactic acid fermentation is the method by which glucose and other carbohydrates are converted into lactate and energy. This takes place under the condition of insufficient oxygen. This process is similar to glycolysis till the pyruvate and 2 ATP is produced. Further, the lactic acid is produced from the pyruvate by the process of reduction. The reaction is catalysed by lactate dehydrogenase and the reducing energy is produced.

Lactic acid fermentation is seen on the skeletal muscles during strenuous exercise. Due to the insufficient supply of oxygen, the muscle cells undergo lactic acid fermentation and produce energy. This results in the accumulation of lactic acid in the muscles which causes fatigue.

Note: Another example od lactic acid fermentation is seen in Lactobacillus. This bacterium is used in the milk processing industry to produce curd and yoghurt. The fermentation process is beneficial for the human intestine as it aids in digestion and keeping the gut flora healthy.