Breathing and Exchange of Gases – Notes

Respiratory Organs
The process of breathing accompanied by the breakdown of foods to produce energy is called respiration.
Among all animals, mammals have a well-developed respiratory system.
In humans beings, and generally in all mammals, the organs of respiration include the nose, pharynx, larynx, trachea, bronchi, lungs and diaphragm.
Based on function, the respiratory system is divided into two parts- the conducting part and the respiratory part.
The conducting part spreads from the external nostrils to the terminal bronchioles.
The respiratory part contains the alveoli and alveolar ducts.

Mechanism of Breathing
Respiration involves: breathing, external respiration, internal transport, internal respiration and cellular respiration.
As carbon dioxide is twenty to twenty five times more soluble than oxygen, the amount of carbon dioxide that can diffuse through the diffusion membrane is much higher compared to that of oxygen.