Breath regulation

People can stay for a few seconds without breathing. It is also possible to breathe faster or slower. In these situations, breathing is controlled voluntarily, that is, as the person wishes, and activity of the diaphragm and intercostal muscles is regulated by a region of the person's brain.

However, when a person is not "thinking" about breathing or sleeping, for example, diaphragm and intercostal muscle activity is regulated by an organ of the nervous system called the bulb, located just below the brain. This control is involuntary, independent of our will. The bulb has a group of neurons that controls the breathing rhythm.

A person cannot hold their breath beyond time even if they wish to. By stopping breathing, carbon dioxide is no longer excreted by the person's blood into the external environment. The concentration of this gas increases in the blood and, upon reaching a certain level, the bulb restarts breathing, regulating the contraction and relaxation activity of the diaphragm and intercostal muscles. The person then resumes breathing even if they do not want to.

Human health and the respiratory system

As we have seen, the oxygen contained in atmospheric air reaches the interior of our body through the respiratory system.

With air, in addition to oxygen can be absorbed other substances, dust particles, soot, and even microscopic living beings, such as viruses and bacteria, which can cause harm to our health. Some impurities are "filtered" out of various organs of the respiratory system, but others can pass into the lungs, causing disease. The most common diseases affecting the respiratory system may be infectious or allergic in nature.

Infectious diseases

Flu and Cold

Influenza is a very common and infectious disease caused by the influenza virus, discovered in 1933. There are reports of the flu since the 5th century BC, in the time of Hippocrates. From then on several reports were made describing the deaths of millions of people as a result of the flu. These epidemics were seen in the past as a consequence of the influence of the stars, hence the name of the virus: Influenza.
There have been some serious flu epidemics throughout history, such as Spanish, Asian, and Hong Kong flu. Based on the results of the three largest pandemics in history, there are more than 1.5 million people killed and a $ 32 billion loss. In fact, nowadays influenza is not a worrying disease, since the disease generally evolves benignly, without the need for major therapeutic measures, and there is a vaccine to prevent it.
The disease is highly contagious, its transmission occurs through the particles of an infected person's saliva, expelled through breathing, speaking, coughing and sneezing. In addition, the incubation period for influenza is on average 2 days.
Symptoms of the disease are: malaise, high fever (38-39ºC), chills, muscle aches, headache, runny nose, stuffiness. Influenza can become severe, especially for the elderly, pregnant or debilitated by chronic diseases.
The flu usually ends naturally, as a result of each individual's immune capacity. It is advisable to get plenty of rest and eat well; drink plenty of fluids such as fruit juices or water; moisten environments as much as possible; Use tissues when coughing or sneezing to prevent contamination of others and seek medical advice.


Bronchitis is the inflammation of the bronchi which occurs when your tiny eyelashes stop removing mucus from the airways. This accumulation of secretion causes the bronchi to become permanently inflamed and contracted. Bronchitis can be acute or chronic. The difference is the duration and worsening of seizures, which are shorter (one or two weeks) in acute bronchitis, while chronic ones do not disappear and worsen in the morning.

Acute bronchitis is usually caused by viruses, although in some cases it may be a bacterial infection. Cigarette is the main responsible for the aggravation of the disease. Dust, environmental pollutants and chemicals also make the picture worse.

Chronic bronchitis sets in as an extension of acute bronchitis and can be caused solely by cigarette smoke. This is why it is known as “smokers cough” because it is rare among non-smokers.

In both acute and chronic forms, cough is the main symptom of bronchitis. Dry or productive cough may be manifestations of acute bronchitis. In the chronic, however, the cough is always productive and the sputum thick. Shortness of breath and wheezing are other symptoms of the disease.