What is the respiratory center?

We don't have to worry about that intercostals muscles and diaphragm 16 times per minute produced respiratory movements. These muscles controls respiratory center, lying in the medulla near the centres that control the heart and blood vessels. In respiratory center rhythmically with some frequency arise excitation going to the muscles. Respiratory center are exposed to many reflex influences.
So, if on the mucous membrane of the trachea or bronchus gets large foreign particle (a morsel of food when podergivani and so on), this part is, irritating, sends impulses to the breathing center, which in response causes a sharp exhale when approached vocal cords. Jet air force passing through a narrow slit carries harmful particles. Thus arises the cough is an important defender of the body to counter the blockage of the respiratory tract. When inflammation cough removes accumulated mucus dead bodies of microbes. If irritation exposed mucous of the nose, the stream of air at the same increased exhalation goes through it is sneezing. Groups of nerve cells that control these complex reflexes, called centres of coughing and sneezing. They are associated with respiratory center.
Important influence on the activity of the respiratory center render the signals coming from the lungs. At the height of inspiration signals about the stretching of light running along the wandering nerve to the brain, as a result, the breath stops and the exhalation. Less than stretched becomes light, the lower the signal goes to the brain, and at the end of exhalation again excited by the group of cells of the respiratory centre, which is responsible for breath.
Especially large effect on the respiratory centre provides blood levels of carbon dioxide, i.e. here the prominent role of humoral regulation. Each of us knows from experience that if you try to hold your breath, then after a few seconds, you receive an irresistible desire to breathe. In the end we already unable to restrain the movements of the respiratory muscles and breathing resumes. What's so hard initiate breathing centre with breath?
If you bind on the operating table next two dogs, cut them carotid artery (feed the brain) and fasten them evenly, i.e. so that the blood of one dog had a head another, you can find the answer to our question. When you pinch your nose and mouth of one of the dogs, panting begins another. It appears shortness of breath. So, here the main role is played by the change in the composition of blood. Oxygen-poor and rich in carbon dioxide blood of the first dog entered in the carotid artery another. Here she irritate the sensitive nerve endings, which ran impulses to respiratory center. Further blood washes directly region of the respiratory center. The second dog begins shortness of breath - shortness of breath.
Another, much simpler experience also shows us that the most important stimulus of the respiratory center is the composition of blood. Check to see how many seconds you will not be able to breathe after the usual deep breath. Then hard, too breathe for 30-40 seconds; this excess breath is called hyperventilation. Now repeat the experience with breath. You will see that the duration of her more than double. By hyperventilation you remove from the blood more carbon dioxidethan usual, and besides, so enrich 3 liters of alveolar oxygen, and that at the next breath the first half of the time it takes to restore normal levels of carbon dioxide in the blood and use the excess oxygen, which is available in the lungs. Only after that begins changing gas composition of the blood in an unfavorable direction, forcing eventually resume breathing. In this way - hyperventilation - use seekers pearls in the southern countries, conveyed by training the duration of stay under water for up to 5 minutes. Such a method existed since ancient times and acted more reliable aqualung.