*Regulation of oxygen partial pressure takes place at high altitude.
*Does not involve central chemoreceptors.
- At high altitude, the atmospheric pressure is low.
- The partial pressure of oxygen in the atmosphere is low.
- The partial pressure of oxygen in the blood decreases.
- This is detected by the peripheral chemoreceptors (aortic bodies and carotid bodies).
- Nerve impulses are generated and sent to the respiratory center in the medulla oblongata.
- Respiratory center sends nerve impulses to the effectors (diaphragm and intercostal muscles).
- Diaphragm and intercostal muscles contract and relax faster.
- Breathing rate increases.
- More oxygen is inhaled.
- Partial pressure of oxygen in blood returns to normal.