Question 21

Lactic acid is associated with a burning sensation as a result of anaerobic respiration.

During anaerobic respiration, lactic acid accumulates in the muscles, leading to a burning sensation often experienced during intense exercise.

A) Carbon dioxide

Carbon dioxide is a byproduct of both aerobic and anaerobic respiration. While it can contribute to the physiological responses during exercise, it is not directly responsible for the burning sensation associated with anaerobic conditions.

B) Lactic acid

Lactic acid is produced when glucose is metabolized anaerobically, especially during high-intensity workouts. Its accumulation in muscle tissue is what leads to the characteristic burning sensation, making this option the correct answer.

C) Oxygen

Oxygen is essential for aerobic respiration, not anaerobic respiration. In fact, the lack of oxygen is what triggers anaerobic pathways, and thus it does not contribute to the burning sensation experienced during anaerobic conditions.

D) Glucose

While glucose is the substrate used during both aerobic and anaerobic respiration, it does not cause the burning sensation directly. Instead, it is broken down into lactic acid in the absence of oxygen, which is the compound responsible for the feeling of burn.

Conclusion

Lactic acid is definitively the correct answer as it is the compound that accumulates during anaerobic respiration, causing the burning sensation in muscles. In contrast, carbon dioxide, oxygen, and glucose do not directly lead to this sensation, making them incorrect choices in this context.