Respiratory system: features, parts, functions and diseases

The respiratory system refers to the set of organs possessed by living things in order to exchange gases with the environment.. This cold definition is postulated soon, but the concept is put more into perspective when you consider that oxygen is the engine of cellular work, with all that that implies.

Mitochondria (cell organelles) convert glucose and oxygen into high-energy bonds that can be stored in ATP and used by the cell for its metabolism. We can therefore safely say that with water, the air in the environment makes life as we know it possible.

That is why to cover the gigantic world of the respiratory system, we need a multidisciplinary approach: we do not have enough to focus on its morphology, but we also need to explore what happens in the event of failure and the digital data that supports its importance. If you want to get a general idea of ​​this exciting physiological conglomerate, keep reading.

    Respiratory system: its main characteristics

    According to the Royal Spanish Academy of Language, the term “system” in its most biological sense is defined as a set of organs involved in some of the main vegetative functions of living things. In this case, there is no doubt that we are facing the phenomenon of respiration, Who is called soon.

    To begin to dissect this web of networks and biological mechanisms, we can focus on the parts of this apparatus. Let’s go.

    Parts of the respiratory system

    It should be noted that the respiratory system is made up of three different parts.

    First, we have a portion of conductive air (nasal cavities, bronchi, bronchioles … etc), or what is the same, a series of branched tubules through which gases flow.

    Beyond that, we can also distinguish a respiratory part for gas exchange, where the most “bloody” component of the system comes into play (for example here the alveoli and their capillaries are included). Finally, to close this triad, living beings present a ventilatory mechanism, which “pumps” the entry and exit of gases from our body (rib cage and intercostal muscles, for example).

    We are faced with a system of complex evolutionary origin that imitates machinery of exquisite sophistication (or rather the reverse, since each machine is based on physical and biological processes).

    This device comprises a series of highways and circulation channels (conductive part), a material exchange center (cells and associated circulatory parts) and a pumping device which exerts the pressures necessary for the operation of the “machine”. , Rib cage and diaphragm). All these elements are perfectly punctuated by maximize the individual’s energy gain at all times.

    Yes, we could present you with a list of all the organs and structures associated with this device: nostrils, larynx, pharynx, trachea, lungs, diaphragm … etc, but we would be missing a lot of relevant information that you might not know . Remember: to understand a system, even in general, one should not be limited only to their physiological structures. So let’s jump into the world of breathing.

      Breathing and its numbers

      “Breathing” is the process by which living things exchange gases with the outside environment. What not many people know is that this term has another meaning, as it is also considered to be respiration in the set of biochemical reactions by which certain organic compounds are completely broken down, by oxidation, to become inorganic substances. . As you may have guessed, it is cellular respiration, or what is the same thing, the process of obtaining energy.

      We will focus on the first definition of the term: pulmonary respiration (in vertebrates, as other animals breathe through the trachea or gills). As a general concept, we can state that the process of inhaling and exhaling is a game of pressure. Intrapleural pressure, intrathoracic volume, associated musculature and diaphragm vary in position and functionality, so this mechanical activity can be performed without problems. How does this translate into objective numbers?

      • Humans breathe in and out between five and six liters of air per minute.
      • In 24 hours, a healthy person inhales and exhales approximately 8,000 liters of air.
      • In the breaths as such, this translates to about 21,000 per day.
      • For this exchange, each human brings a little more than one kilogram by weight of CO2 to the atmosphere every day.

      This data puts things in perspective, right? Due to the functionality of the respiratory system, the oxygen content in the body of all living things is higher in the organs involved in this process, but it decreases in any arterial and venous system.. This oxygen content is quantified by the partial pressure, that is to say the theoretical pressure of the gas if it occupied the entire volume of the original mixture. The alveolar pressure of pulmonary gases is 14.2 Kpa (kilopascals).

      All of these data and figures are of great interest, but all that glitters is not gold. Such a complex system requires an exquisite integration of all its components, And unfortunately, this is not always the case.

        Diseases of the respiratory system

        We have talked about the parts of this device and the breathing process, but we cannot leave in the inkwell what happens in the event of a breakdown. The World Health Organization gives us the following data:

        • About 235 million people (7% of adults) suffer from one of the most common respiratory disorders: asthma.
        • In 2016, more than 400,000 people died from asthma. In the past, it was estimated that 80% of deaths occur in low-income countries.
        • Chronic Obstructive Pulmonary Disease (COPD) affects more than 200 million people worldwide.
        • The latter figure is even worse when you consider that several studies indicate that up to 90% of cases go undiagnosed.
        • Pneumonia is responsible for 15% of deaths in children under five.

        We could continue to expose this data for years to come. Respiratory diseases can be caused by bacteria, viruses, helminthic parasites, allergies, immune system dysfunctions, cancer, hereditary diseases and many other causes. essentially anything that can get into the upper or lower airways can cause pathology.

        To such an extent comes the apparent vulnerability of the respiratory system which can develop into fungi in the lungs. This is the case of bronchopulmonary aspergillosis and invasive pulmonary aspergillosis, Pathologies caused by the fungus of the genus Aspergillus.

        The lethality of this disease is such that, if it spreads through the organs of the patient, the death rate can reach over 87%. For the relief of readers, this condition only occurs in people who are immunocompromised or have severe breathing problems.

        Another of the queens of respiratory tract pathologies is, without a doubt, lung cancer. In Spain, around 18,000 people die each year from this malignant tumor process, which corresponds to 27% of all cancer deaths. Smoking is associated with up to 90% of lung cancer deaths, so recommendations are made on their own.


        As we have seen, the respiratory system gives us a cold and a hot one. On the one hand, it is an exciting device that exactly integrates the functions of various organs and structures, but on the other hand, its dysfunction and disorders can end the patient’s life, Depending on your immune status, your place of origin and your lifestyle.

        Again once we are not just moving into a physiological realm, for beyond the tissues and structures that give form and name to a system, there is a compelling digital data set that is often overlooked when tackling issues. questions of such a concrete nature.

        bibliographical references:

        • Respiratory system, student resources of the University of Alcalá de Henares (UAH). Collected at 25 p.m. September at
        • Lung cancer, AECC. Collected September 25 at A1ncer% 20de% 20pulm% C3% B3,% 25% 20del% 20total% 20de% 20muertes).
        • How the Lungs Work, National Heart, Lung, and Blood Institute (NIH). Collected September 25 from ADgeno% 20a% 20La% 20sangre% 20y, a% 20hacer% 20posible% 20La% 20respiraci% C3% B3.
        • Chronic respiratory disease, World Health Organization (WHO). Collected September 25 at
        • Pérez-Arellano, JL, Andrade, MA, López-Abán, J., Carranza, C., and Mur, A. (2006). Helminths and the respiratory system. Bronchopneumology Archives, 42 (2), 81-91.
        • The Global Impact of Respiratory Disease, World Health Organization (WHO). Retrieved September 25, from

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