The document discusses gas exchange in humans and how the body controls breathing and heart rate to maintain optimum oxygen levels. It explains that chemoreceptors in the aorta, carotid artery and brain detect changes in oxygen levels and signal the body to increase or decrease ventilation and heart rates accordingly to keep oxygen at optimal concentrations in the blood.

1. Gas Exchange in Humans The control of the rate of breathing (ventilation)

2. Optimum concentration of oxygen in blood

3. Optimum concentration of oxygen in blood Increase in oxygen

4. Optimum concentration of oxygen in blood Increase in oxygen

5. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain

6. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain

7. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate)

8. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate)

9. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate) Decrease in oxygen

10. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate) Decrease in oxygen Optimum concentration of oxygen in blood

11. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate) Decrease in oxygen Optimum concentration of oxygen in blood Decrease in oxygen

12. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate) Decrease in oxygen Optimum concentration of oxygen in blood Decrease in oxygen

13. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate) Decrease in oxygen Optimum concentration of oxygen in blood Decrease in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain

14. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate) Decrease in oxygen Optimum concentration of oxygen in blood Decrease in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain

15. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate) Decrease in oxygen Optimum concentration of oxygen in blood Decrease in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Increase in ventilation rate (and in heart rate)

16. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate) Decrease in oxygen Optimum concentration of oxygen in blood Decrease in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Increase in ventilation rate (and in heart rate) Increase in oxygen

17. Optimum concentration of oxygen in blood Increase in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Decrease in ventilation rate (and in heart rate) Decrease in oxygen Optimum concentration of oxygen in blood Decrease in oxygen Detected by chemoreceptors in aorta, carotid artery, and medulla oblongata in brain Increase in ventilation rate (and in heart rate) Increase in oxygen