Question

How does respiration take place in muscles? Give the equation for the same.

Answer 1

Hint: The process of respiration takes place in muscles depending upon the availability of oxygen. It would be either aerobic or anaerobic respiration. Normally, in muscle cells, aerobic respiration takes place. But at times of higher energy needs like running fast or vigorously exercising, the muscle cells work faster and require more energy. The muscle cells switch over to anaerobic respiration to meet this kind of energy requirement.

Complete answer:
Normally in our body, the muscle cells carry out aerobic respiration. Aerobic respiration is the process of cellular respiration which takes place in the presence of oxygen to produce energy from food. This is the most common type of respiration that is seen in plants and animals, birds, humans, and other mammals. Water and carbon dioxide are produced as end products in the process of aerobic respiration.
Aerobic respiration can be given by the equation: $$Glucose+Oxygen\to Carbon-dioxide+Water+Energy$$
But higher energy is required at times of heavy exercise or running fast the muscle cells work faster and require more energy. At this time to meet this energy requirement, the muscle cells switch over to anaerobic respiration from normal aerobic respiration. But in this case, partial breakdown of glucose takes place and produces lactic acid. This builds-up lactic acid in muscles and the lactic acid needs to be oxidized to carbon dioxide and water later.
Anaerobic respiration can be given by the equation: $$Glucose\to Lacticacid+Energy$$

Note:
Aerobic respiration takes place in the mitochondria whereas anaerobic respiration takes place in the cell cytoplasm. When muscle cells respire anaerobically, cramps are formed. The partial breakdown of glucose which takes place due to the lack of oxygen produces lactic acid and the accumulation of lactic acid causes muscle cramps. That is why it is recommended to take a hot shower after heavy sports which relieve the cramps as it improves blood circulation in the body and enhances the supply of oxygen to the cells.