1. HCS 1070 SLO: 1.10 Respiratory Regulation

2. Chemical Control
Respiration is controlled by chemoreceptors that are sensitive to chemicals dissolved in body fluids.
Chemoreceptors are located centrally near the brain stem and peripherally in the arteries.

4. Central Chemoreceptors
These receptors can be found on either side of the brain stem near the medulla oblongata
It responds to CO2 levels circulating in the blood and to the Hydrogen ions as the CO2 is converted into bicarbonate and H+ (sensitive to the change in pH)
Hypercapnia is the rise in blood CO2 levels and this triggers ventilation

5. Peripheral Chemoreceptors
These structures are not found in the brain but are located in the carotid and aortic arch.
These contain sensory neurons that respond mainly to a decrease in oxygen supply
They are not usually involved in regulating breathing because they do not act until oxygen drops to a very low level.

6. Ultimately, carbon dioxide then has the most immediate effect in regulating respiration.
When carbon dioxide levels increase, breathing must be increased to blow off the excess gas

7. Hyperventilation
This condition results from deep and rapid respiration that commonly occurs during anxiety attacks, or when a person is experiencing pain or other forms of stress
Hyperventilation causes an increase in the oxygen levels and a decrease in carbon dioxide levels

8. This low level of carbon dioxide changes the pH of the blood which causes dizziness and tingling sensations
In extreme cases, a person may faint and then breathing will involuntarily return to normal
To help a person who is hyperventilating, speak calmly and reassuringly and encourage them to take even breaths from the diaphragm

9. Hypoventilation
Caused by insufficient amounts of air entering into the alveoli.
Causes can include:
Respiratory obstruction
Lung disease
Injury to the respiratory center
Depression of the respiratory center(caused by drugs)
Chest deformity

10. Read A Closer Look on pg 415
Adaptations to High Altitude: Living with Hypoxia and complete the questions in your notes booklet