Question

Anaerobic respiration occurs in human body inside
A. Liver
B. Kidney
C. Red muscles
D. White muscles

Answer 1

Hint: Anaerobic respiration is a type of respiration in which breakdown of glucose takes place in the absence of oxygen. Anaerobic respiration produces lactic acid instead of carbon dioxide and water. Examples of this process are Lactic-acid fermentation and decomposition of organic matter.

Complete answer: The anaerobic respiration occurs in the human body inside the white muscles. White muscle fibres are lighter in colour as they do not have myoglobin. Myoglobin binds and stores oxygen as oxymyoglobin in the red muscle fibres. Oxymyoglobin releases oxygen for utilization during muscle contraction. There is less number of mitochondria in white muscles. White muscles carry out anaerobic Oxidation (glycolysis) for energy production and accumulate lactic acid in considerable amounts during strenuous work and soon get fatigued. These muscle fibres have a fast rate of contraction for short periods.
The muscle fibres which are dark red in colour due to the presence of red hemoprotein called myoglobin. Myoglobin binds and stores oxygen as Oxymyoglobin in the red muscle fibres. Oxymyoglobin releases oxygen for utilization during muscle contraction. They have more mitochondria than white muscles. These red muscle fibres carry out aerobic respiration without accumulating much lactic acid and these muscles can contract for a longer period.

So the correct answer is option D.

Note: From the above solution, we came to know that white muscles lack hemoprotein called myoglobin which stores oxygen and aerobic respiration occurs in the presence of oxygen. That’s why anaerobic respiration occurs in white muscles.