The respiratory center is an area located in the pons and the medulla oblongata, the lowest portion of the brain stem.
There are actually four separate areas that together comprise the respiratory center. In the medulla there is the ventral respiratory group, which controls the force of exhalation. The dorsal group controls timing of inspiration. In the pons the apneustic center controls the length if inhalations and helps coordinate the turnover from inhaling to exhaling. It is assisted in this by the pneumotaxic center.
Interestingly, the medulla oblongata does not sense oxygen levels in the blood as you might expect, but instead it contains chemoreceptors which monitor the levels of carbon dioxide and the blood pH. When carbon dioxide dissolves in the blood it becomes carbonic acid, which lowers the blood pH.
The respiratory centers are located at the reticular formation of the stem of the brain in the medulla oblongata and pons. The role of the respiratory centers is to regulate ventilation by collecting information with regards to the level of carbon dioxide and oxygen in the blood and then sending the appropriate signal through the spinal cord to the respiratory muscles. The respiratory centers can be divided into four sections;
- The inspiration center which is located in the dorsal part of the medulla and which is responsible for inspiration upon stimulation
- The expiration center which is located in the antero-lateral section of the medulla and responsible for causing expiration. However, it can also cause inspiration depending on the neuron that has been stimulated.
- The pneumotaxic center that is located in the upper part of pons and whose function is to regulate the rate and pattern of breathing
- The apneustic center which is located in the lower portion of pons
It is located in the brain
specifically its called the Medulla Oblangata. It monitors the body's CO2 and pH levels and sends instructions to the lungs if there is a problem (acidosis or alkalosis).