Respiratory System
Respiratory System

Respiratory System in Human and Animal: Definition, 3 Functions, Work, and Mechanism

Humans in breathing breathe oxygen in free air and dispose of carbon dioxide into the environment. Breathing is a double process that occurs in the exchange of gases in the tissues or “internal respiration” and that occurs in the lungs “External respiration”.

External respiration which is an exchange between O2 and CO2 between blood and air. Internal respiration which is an exchange of O2 and CO2 from the bloodstream to the cells of the body.

In humans, the respiratory system includes a channel used to carry air into the lungs where gas exchange occurs. The diaphragm pulls the air in and also expels it. Various variations of the respiratory system are found in different types of living things.

Respiratory System Definition

The respiratory system is a collection of organ tissue that helps the body breathe.

The respiratory system helps the body absorb oxygen from the air and remove residual gases such as carbon dioxide from the blood.

With the support of oxygen, the entire organ can function normally.

Respiratory System Function

The respiratory system has many functions.

Not only helps you breathe, but other functions of the respiratory system are:

  • Make you talk and smell something
  • Flow air, according to body temperature and moisture it according to body condition
  • Protects the airways from harmful substances and irritation.

How human respiratory system works?

  1. When you inhale, air enters through the nasal cavity or is also referred to as the process of inspiration. Then, the process of filtering small particles that enter with air occurs in the nasal cavity by cilia.
  2. The incoming air is adjusted for temperature and pressure through the sinuses.
  3. After that, air enters the trachea or windpipe. Here the air will be filtered into two bronchial tubes leading to the lungs.
  4. Then the air enters the lungs and is channeled into the bloodstream.
  5. Red blood cells will flow oxygen to the parts of the body that need to work properly. Red blood cells also collect carbon dioxide from the body’s cells and return it to the lungs.
  6. Inside the alveoli, an exchange between oxygen and carbon dioxide occurs. Carbon dioxide will come out as you exhale.
  7. Then, the diaphragm muscles control breathing. The diaphragm muscle will deflate and pull forward as you inhale oxygen and expand as the air comes out of the lungs.

That’s how the human respiratory system works. It turns out that the respiratory system has a long process until oxygen is circulating throughout the body and keeps you alive.

Human respiratory system mechanism

Breathing is a process that occurs automatically, even in a state of sleep because the respiratory system is influenced by the autonomic nervous system.

According to the place of gas exchange, breathing can be distinguished by 2 types, namely external respiration and internal respiration. External respiration is the exchange of air that occurs between the air in the alveolus and the blood in the capillary, while internal respiration is the breathing that occurs between the blood in the capillary and the cells of the body.

The entry and exit of air in the lungs are affected by differences in air pressure in the chest cavity with air pressure outside the body. If the pressure outside the chest cavity is greater then the air will enter. Conversely, if the pressure in the chest cavity is greater then the air will come out.

With respect to the organs involved in air entry (inspiration) and air expiration, then the respiratory mechanism is distinguished by two kinds, namely chest breathing and belly breathing. Chest and belly breathing occurs simultaneously.

Chest Breathing

Chest breathing is a breathing that involves the muscles between the ribs. The mechanism can be distinguished as follows.

Inspiration phase

This phase is in the form of contracting the muscles between the ribs so that the chest cavity enlarges, as a result of which the pressure in the chest cavity becomes smaller than the pressure outside so that the oxygen-rich outer air enters.

Expiration phase

This phase is a phase of relaxation or return of muscles between the ribs to their original position followed by the lowering of the ribs so that the chest cavity becomes small. As a result, the pressure inside the chest cavity becomes greater than the external pressure, so that the air in the chest cavity rich in carbon dioxide comes out.

Belly Breathing

Belly breathing is a breathing mechanism that involves the activity of diaphragm muscles that limit the abdominal cavity and chest cavity.

The belly breathing mechanism can be distinguished into two stages, namely the following.

Inspiration Phase

In this phase the diaphragm muscles contract so that the diaphragm flattens, as a result of which the chest cavity enlarges and the pressure becomes small so that the outside air enters.

Expiration Phase

The expiration phase is the relaxing phase of the diaphragm muscle (returning to its original position, expanding) so that the chest cavity shrinks and the pressure becomes greater, as a result of which the air comes out of the lungs.

Animal respiratory system

The respiratory system in animals has a slightly different structure. Here are some examples of respiratory systems in some animals:

  • The respiratory system in the Porifera and coelenterata is performed by diffusion directly through the cell membrane.
  • The respiratory system in worms is called integumentary respiration which is performed diffusion by the always damp surface of the skin
  • The respiratory system in most insects, uses a respiratory apparatus in the form of tracheal vessels.
  • The respiratory system in fish uses gills.
  • The respiratory system in frogs uses gills when it is still in the form of tadpoles while older frogs breathe with the lungs when on land and use the skin when in water.
  • The respiratory system in reptiles uses the lungs.
  • The respiratory system in birds uses the lungs, but has no alveolus but parabronchi (air vessels). Respiration when flying using airbags, while at rest using the lungs.

Read also:
Excretory System: Definition, and Organs

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Respiratory System in Human and Animal: Definition, 3 Functions, Work, and Mechanism

Post in | Last updated: January 21st, 2021 |