We explain what the respiratory system is, what its organs and functions are, as well as its characteristics and possible diseases.
What is the respiratory system?
The respiratory system is the set of organs involved in breathingThis system is responsible for the distribution of oxygen in the body. It is responsible for capturing oxygen and removing carbon dioxide from the body.
The organs of the respiratory system They are not found in all living beings in the same way. Some animals have a type of respiration in which the cells do not transport oxygen to the rest of the body. Rather, their breathing is cutaneous type. Examples of these animals are sponges or coelenterates.
Some beings have a respiratory system made up of gills. Others, for their part, have lungs. It is said that, in terms of evolution, gill respiration is more primitive than lung respiration.
Regarding the respiratory system of human beings, this It has lungs and takes 26,000 breaths a day while a baby breathes up to 51,000 times a day.
Organs of the respiratory system
The respiratory system is made up of different organs: nasal cavities, nasal cavity, oral cavity, pharynx (which is also part of the digestive system), larynx (here the vocal cords are located), epiglottis (responsible for closing the trachea while the person is eating), trachea (cartilaginous tubes that retain dust particles), bronchi, bronchioles, pulmonary alveoli and lung.
Functions of the respiratory system
The main functions of the respiratory system are:
- Provide the oxygen necessary for the organism to live. When a person inhales, he or she takes in oxygen. The respiratory system is responsible for transporting it to the blood to provide oxygen to the different organs of the body.
- Eliminate carbon dioxide from it, by exhaling the air.
- To heat the air that is inspired.
- Filter and clean the same oxygen.
Airways
For its study it is classified into 2 zones.
- Driving area. This includes all the anatomical zones that oxygen passes through before reaching the next zone (respiratory zone).
- Respiratory zone. It is the area where gas exchange occurs.
Types of alveolar cells
In the respiratory system there are two types of cells that perform different functions:
- Type I pneumocytes. These cover between 95% and 97% of the total surface of the lungs.
- Type II pneumocytes. These cells are found in smaller quantities (only between 3% and 5%). They secrete a substance called pulmonary surfactant. This substance prevents tension within the alveoli. In this way they prevent them from collapsing. This surfactant is composed of phospholipids and proteins.
Properties of the lungs
- Adaptability. That is, the lungs exchange air. This produces some expansion or dilation of the lungs.
- Elasticity. Although they have the peculiarity of dilating, they contract thanks to this elasticity that they have and which is necessary thanks to the fact that they have elastin proteins.
- Surface tension. It refers to the tension that occurs within the alveoli.
Muscles that act in the respiratory system
Although the muscles do not belong to this respiratory system, they act and intervene in breathing.
- The muscles involved in inspiration:
- Sternocleidomastoid
- scalenes
- External intercostals
- Para-sternal intercostals
- Diaphragm
- The muscles involved in expiration:
- internal intercostals
- External oblique of the abdomen
- internal oblique abdominis
- transverse abdominis
- Rectus abdominis
Pulmonary ventilation
It is a process that allows both the movement of air into the lungs (inspiration) and out (expiration). Although only two moments appear here, there is certainly another moment that is rarely taken into account: the moment without expiration or inspiration. That is, the moment of rest.
Lung capacity
There are different volumes of oxygen that enter the lungs. They are differentiated between:
- Tidal volume. It is the normal or usual volume that enters the lungs.
- Inspiratory reserve volume. This is the name given to the type of oxygen that enters the lungs excessively and in a forced manner.
- Expiratory reserve volume. It is the amount of air that leaves the body in a forced and excessive manner.
- Vital capacity. It refers to the amount of air that can be exhaled after a forced inhalation.
- Residual type volume. It is the amount of air that remains permanently inside the lungs. In the case of adult humans this amount can be up to 1.5 liters.
- Total lung capacity. It is the maximum amount that the lungs can hold.
Unusual functions of breathing
- Cough. It is a reflex action that can come from the nervous, respiratory or digestive system.
- The hiccups. It is an involuntary contraction of the diaphragm.
- The sneeze. Which occurs as a response to irritation from dust particles or odors.
- Yawning. Related to the nervous system and is associated with physical and mental fatigue and the person’s sleep levels. This is also a way to increase blood supply to the brain.
- The sigh. It is a way to level the volume of air entering the brain.
- Laughter. From the point of view of the respiratory system, laughter involves a series of actions that release air from the body in a short, weak and intermittent manner.
Diseases of the respiratory system
Some specific diseases or pathologies that affect the respiratory system:
- Bronchial asthma
- Pulmonary edema
- Lung infarction
- Respiratory insufficiency
- Viral or bacterial infectious diseases.
- Lung cancer, larynx cancer, trachea cancer, pharynx cancer, etc.