The body monitors the levels of oxygen in the blood to regulate breathing. Isabel is running in a marathon and is near the finish line. She feels out of breath. How will her nervous system work to generate a reaction?

Low oxygen pressures in the blood cause the nervous system to respond with hyperventilation.

Explanation:

In our body, the partial pressures of oxygen in the blood is a marker of blood pressure and hyperventilation.

The partial pressure of this gas may be decreasing due to lack of partial pressure of oxygen in the atmosphere that we breathe or in the great respiratory demands, that is why in this case, the partial pressures of oxygen during the marathon decrease.

When decreasing, this is captured by the nervous receptors and the CNS executes an increase in respiratory rate, generating hyperventilation so that the partial pressure of oxygen increases.

These receptors are chemoreceptors, capable of detecting the slight drop in blood pH due to oxygen deficiency associated with hemoglobin, since metabolic acidity is very common in cases of low oxygenation.

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