How oxygen is extracted from air in lungs?

 Oxygen extraction from the lungs is a biological engineering marvel necessary for aerobic species like humans to survive. This complex process occurs in the lungs, where the respiratory system exchanges oxygen and carbon dioxide between air and blood.

Inhalation:

The journey begins with breathing. The diaphragm contracts and the ribcage expands, expanding the thoracic cavity. This expansion lowers lung air pressure, allowing oxygen-rich outside air to enter through the nose and mouth.

Airways:

The trachea (windpipe) and bronchial tubes carry breathed air to the alveoli.

Alveoli:

Gas exchange happens in the lungs' grape-like alveoli. These air sacs are surrounded by several thin-walled capillaries.

Diffusion:

Gas exchange relies on diffusion. Air oxygenates the capillaries through the alveoli's thin walls. CO2, a waste product of cellular respiration, passes from capillaries to alveoli for expiration.

Binding hemoglobin

Once in the bloodstream, oxygen attaches to red blood cell hemoglobin. Blood proteins like hemoglobin carry oxygen to cells and organs.

Circulation:

The circulatory system delivers oxygen-loaded red blood cells to every body part. Hemoglobin transports cellular metabolism-produced carbon dioxide to the lungs.

Exhalation:

The procedure ends with exhalation. Diaphragm relaxation and ribcage contraction reduce thoracic cavity volume. This increase in lung pressure expels carbon dioxide-rich air into the outside world.

This coordinated dance of breathing, diffusion, circulation, and expiration supplies oxygen to cells and efficiently removes carbon dioxide, maintaining life's delicate balance. This elegant and precise procedure shows the human respiratory system's complexity, demonstrating how living organisms have adapted to flourish.