Structure and Function of Different Parts of Respiratory Organs

Oxygen (O2), which is necessary to obtain energy from food, is a key necessity for all bodily cell activity and growth. One of the main waste products from these actions is carbon dioxide (CO2).

Through a series of passageways provided by the respiratory system, oxygen from the ambient air is delivered to the individual tissue cells, while carbon enters the body and CO2 exits it to remove their gaseous waste products. The respiratory system's primary function is to release carbon dioxide. As a result, the respiratory system can be seen as an airway connecting the atmosphere and the blood.

By facilitating the exchange of gases (02 and CO2) between atmospheric air, blood, and tissue cells, the respiratory system helps maintain homeostasis.

Upper and lower respiratory tracts are two ways to categorize the respiratory system. The components of the lower respiratory system are found inside the chest cavity, while the components of the upper respiratory tract are found outside the chest cavity.

Respiration is the process by which a living organism and its surroundings exchange gases (02 from the atmosphere to tissues and CO2 from tissues to atmosphere).

Organs of the Respiratory System:

The following organs are part of the respiratory system:

• Nose and nasal cavity
• Pharynx
• Larynx
• Trachea
• Bronchi, bronchioles, and alveoli
• Lungs

The airways of the nose, nasal cavities, pharynx, larynx, and upper trachea make up the upper respiratory tract.

The lower trachea, bronchi, and lungs make up the lower respiratory system.

The conducting and respiratory zones are the two functional divisions of the respiratory tract's architecture. The network of connected air tubes known as the conducting zones is intended to supply air to the system. The nose, pharynx, larynx, trachea, bronchi, bronchioles, and terminal bronchioles are some of them. The real location of gas exchange is the respiratory zone. These comprise the alveoli, alveolar ducts, respiratory bronchioles, and alveolar sac.

Functions of the Respiratory System:

• The respiratory system exchanges the gases, supplying the organism with oxygen and expelling carbon dioxide.
• The expulsion of CO2 from the organism by the respiratory system controls the acid-base balance.
• Through the removal of some water and heat during expiration, this system keeps the temperature stable.
• It houses the nose, one of the sensory organs responsible for scent.

Volumes and capacities of lungs:

• Tidal Volume (TV):
  • During calm, relaxed breathing, tidal volume refers to the amount of air that is transported into or out of the lungs. At repose, it is around 500ml.
• Inspiratory Reserve Volume (IRV):
  • This term refers to the additional air that can be forcedly inhaled during maximum inspiration. There are roughly 3000ml.
• Expiratory Reserve Volume (ERV):
  • ​​​​​​​Expiratory reserve volume refers to the biggest amount of air released during maximum expiration. around 1200 ml.
• Inspiratory Capacity (IC):
  • ​​​​​​​Inspiratory Capacity Inspiratory capacity is the amount of air that can be forcefully inhaled following a typical tidal expiration.
  • IC = IRV+ TV = 3000+500ml = 3500ml
• Residual Volume (RV):
  • ​​​​​​​After a vigorous expiration, the amount of air still in the lungs' alveoli is referred to as residual volume. around 1200 ml.
• Functional Residual Capacity (FRC):
  • ​​​​​​​The functional residual capacity is the amount of air that is still in the lungs after a typical expiration. It is the result of adding the expiratory reserve volume and residual volume.
  • FRC=RV+ERV= 1200+1200ml = 2400ml
• Vital Capacity (VC):
  • Vital capacity is the amount of air that can be expended from the lungs during maximum expiration after maximal inspiration. The highest amount of air that can be exchanged during respiration is indicated by this. approximately 4800 ml.
• Total lung capacity (TLC):
  • ​​​​​​​The maximum amount of air that the lungs can hold is called total lung capacity (TLC). It is around 5800–6000 ml.
  • TLC= VC + RV
• Dead space:
  • The dead space is the amount of inhaled respiratory gas that does not participate in gaseous exchange. A typical amount of wasted space is 150 ml.