Where does the Exchange of Gases take place ?

Where does the Gaseous Exchange take place ?

The exchange of gases takes place within the respiratory system in alveoli. The principal task of the respiratory system is to supply the blood with oxygen for the blood to supply oxygen to all body parts. The respiratory system performs this through breathing.

When we breathe, we inhale oxygen and exhale carbon dioxide this is known as the exchange of gases and is the body’s mean of getting oxygen to the blood enters the respiratory system through the mouth and the nose. It is the job of the diaphragm, the carbon dioxide out of the lung, and pulls the oxygen into the lungs.

Carbon-Dioxide and Oxygen Exchange Process

Gas exchange happens in a large number of alveoli present in the lungs and the capillaries around them. The essential work of the respiratory system is to take in oxygen and expel with carbon dioxide for the body. The oxygen enters the lungs and reaches the alveoli.

The layers of cells covering the alveoli and the surroundings vessels are each just a single cell thick and are in close contact with one another, this is called the blood barrier between air and blood is around 1 micron (1/10,000 of a centimeter, or 0.000039 inches) wide. Inhaled oxygen goes through this barrier into the blood in the vessels. So also, the carbon dioxide goes from the blood into the alveoli and is then breathed out.
Oxygenated blood goes from the lungs through the pulmonary veins and into the left half of the heart, which pumps the blood to the whole body. At the same time, carbon dioxide-rich blood comes back to the right part of the heart through the superior vena cava and inferior vena cava. Blood travels through the pulmonary vein to the lungs, where it gets oxygen and discharges carbon dioxide.
To help the retention of oxygen and exhale carbon dioxide, around 5 to 8 liters of air get out of the lungs every minute. Simultaneously, the same amount of carbon dioxide moves from the blood to the alveoli and is breathed out. During exercise, body breadth around 100 liters of air in a minute and extract 3 liters of oxygen.
Three procedures are necessary for the exchange of gases from the air to the blood coursing through the lungs. They are ventilation, diffusion, and perfusion.

  • In the process of ventilation, air moves in and out of the lungs.
  • Diffusion means the unconstrained movement of gases, when the body is at rest, between the gas in the alveoli and the blood in the capillaries of the lungs.
  • Perfusion is the procedure by which the cardiovascular system of the body pumps blood in the lungs.

Fact File

INHALED AIR CONTAINS 20 PERCENT OXYGEN, 0.03 PERCENT CARBON DIOXIDE AND THE REST IS NITROGEN. EXPIRED AIR CONTAINS 16 PERCENT OXYGEN, AND THE CARBON DIOXIDE IS INCREASED OVER A HUNDREDFOLD TO 4 PERCENT.