Respiratory system: characteristics, parts, functions and diseases.

Summary of the parts and functions of the nervous system of the human body, and its diseases.

The respiratory system refers to the set of organs that living beings have in order to exchange gases with the environment.. This cold definition is soon postulated, but the concept is put into perspective when we consider that oxygen is the engine of cellular work, with all that this entails.

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

That is why covering the massive world of the respiratory system requires a multidisciplinary approach: it is not enough to focus on its morphology, but we must also explore what happens when it fails and the numerical data that support its importance. If you want to get an overview of this exciting physiological conglomerate, read on.

Respiratory system: its main characteristics

According to the Royal Spanish Academy of the language, the term "system" in its most biological meaning is defined as a set of organs involved in any of the main vegetative functions of living beings. In this case, there is no doubt that we are dealing with the phenomenon of respirationwhich is soon to be said.

To begin dissecting this web of biological networks and mechanisms, we can focus on the parts of this apparatus. Here we go.

The parts of the respiratory system

It is necessary to clarify that the respiratory system is composed of three different parts.

First, we have an air-conducting portion (nasal cavities, bronchi, bronchioles, etc.), or in other words, a series of branched tubules through which gases circulate. through which gases circulate.

Beyond this, we can also distinguish a respiratory portion for gas exchange, where the more "blood" component of the system comes into play (e.g. here we include the alveoli and their capillaries). Finally, to close this triad, living beings present a ventilatory mechanism, which "pumps" the gases in and out of our body (rib cage and intercostal muscles, for example).

We are faced with a system of a complex evolutionary origin that mimics a machine of exquisite sophistication (or rather the other way around, since every machine is based on physical and biological processes).

This apparatus presents a series of highways and channels of travel (conductive portion), a center of exchange of materials (alveoli and associated circulatory parts) and a pumping apparatus that exerts the pressures necessary for the "machine" to function (the musculature, rib cage and diaphragm). All of these elements are perfectly tuned to maximize the individual's maximize the individual's energy output at any given moment..

Yes, we could list all the organs and structures associated with this apparatus: nostrils, larynx, pharynx, trachea, lungs, diaphragm...etc, but we would be missing a lot of relevant information that you may not know. Let us remember: to understand a system, even in a general way, we must not limit ourselves only to its physiological structures, we must not limit ourselves to its physiological structures alone.. So, let's take a leap into the world of respiration.

Breathing and its figures

The process by which living beings exchange gases with the external environment is called "respiration". What not many people know is that this term has another meaning, because it is also considered respiration to the set of biochemical reactions by which some organic compounds are completely degraded, by oxidation, to become inorganic substances. As you may have guessed, this is cellular respiration, or in other words, the process of obtaining energy.

We are going to focus on the first of the definitions of the term: pulmonary respiration (in vertebrates, since other animals breathe by trachea or gills). As a general concept, we can state that the process of inspiration and expiration is a play of pressures. The intrapleural pressure, the intrathoracic volume, the associated musculature and the diaphragm vary in position and functionality so that this mechanical activity can be carried out smoothly. How does this translate into objective figures?

• Humans inhale and exhale between five and six liters of air per minute.
• In 24 hours a healthy person inhales and exhales about 8000 liters of air.
• In breaths as such, this translates into about 21,000 breaths per day.
• Through this exchange, each human contributes a little more than one kilogram by weight of co2 to the atmosphere on a daily basis.

This data puts things into perspective, doesn't it? Due to the functionality of the respiratory system, the oxygen content in the body of any living being is highest in the organs involved in this process, but decreases throughout any arterial and venous system.. This oxygen content is quantified by the partial pressure, i.e. the theoretical pressure of the gas if it were to occupy the entire volume of the original mixture. The alveolar pressure of pulmonary gases is 14.2 Kpa (Kilopascals).

All these facts 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.Unfortunately, this is not always the case.

Diseases of the respiratory system

We have talked about the parts of this apparatus and the respiratory process, but we cannot leave behind what happens when it fails. 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 times 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.
• This last figure is even worse if we take into account that several studies state that up to 90% of cases are undiagnosed.
• Pneumonia is responsible for 15% of deaths in children under five years of age.

We could go on presenting data of this nature for years. Respiratory diseases can be caused by bacteria, viruses, helminth parasites, allergies, immune system dysfunction, cancer, hereditary diseases and many other causes. Basically, anything that can enter the upper or lower airways can lead to pathology..

The apparent vulnerability of the respiratory system is so great that even fungi can grow inside the lungs. This is the case of bronchopulmonary aspergillosis and invasive pulmonary aspergillosispathologies caused by the fungi of the genus Aspergillus.

Such is the lethality of this disease that, if it spreads through the patient's organs, the mortality rate can reach more than 87%. To the readers' relief, this condition only occurs in immunocompromised persons or those with severe respiratory conditions.

Another of the queens of the pathologies of the respiratory tract is, without a doubt, lung cancer, lung cancer.. In Spain about 18,000 people die annually 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 the recommendations are self-evident.

Summary

As we have seen, the respiratory system gives us a lot of trouble. On the one hand, it is an exciting apparatus that integrates the functions of various organs and structures in a precise manner, but on the other hand, but on the other hand, malfunctions and disorders can be life-threatening, depending on the patient's immune status.depending on their immune status, place of origin and lifestyle.

Once again, we are not moving only in a physiological terrain, for beyond the tissues and structures that give shape and name to a system, there are a number of exciting numerical data that are often overlooked when addressing topics of this very specific nature.

Bibliographic references:

• Aparato respiratorio, student resources of the Universidad de Alcalá de Henares (UAH). Retrieved September 25 from https://portal.uah.es/portal/page/portal/epd2_asignaturas/asig650019/informacion_academica/Respiratorio.pdf.
• Lung cancer, AECC. Retrieved September 25 from https://www.aecc.es/es/todo-sobre-cancer/tipos-cancer/cancer-pulmon/evolucion-cancer-pulmon#:~:text=Mortalidad%20del%20c%C3%A1ncer%20de%20pulm%20C3%B3n,%25%20del%20total%20de%20de%20deaths).
• How the Lungs Work, National Heart, Lung, and Blood Institute (NIH). Retrieved September 25 from https://www.nhlbi.nih.gov/health-topics/espanol/como-funcionan-los-pulmones#:~:text=The%20lungs%20make%20entering%20the%20ox%C3%ADGene%20into%20the%20blood%20and,a%20make%20breathing%20possible%20.
• Chronic Respiratory Diseases, World Health Organization (WHO). Retrieved September 25 from https://www.who.int/respiratory/es/.
• Pérez-Arellano, J. L., Andrade, M. A., López-Abán, J., Carranza, C., & Muro, A. (2006). Helminths and the respiratory tract. Archives of Bronchopneumology, 42(2), 81-91.
• The global impact of respiratory diseases, World Health Organization (WHO). Retrieved September 25 from https://www.who.int/gard/publications/The_Global_Impact_of_Respiratory_Disease_ES.pdf.