The respiratory system has several key functions vital to maintaining life and homeostasis. These include:
Primary function: To facilitate the exchange of oxygen (O₂) and carbon dioxide (CO₂) between the air and the bloodstream.
Oxygen is inhaled into the lungs, diffuses into the pulmonary capillaries, and is delivered to tissues.
Carbon dioxide, a waste product of metabolism, diffuses from the blood into the alveoli to be exhaled.
By controlling the levels of CO₂ (which combines with water to form carbonic acid), the respiratory system helps regulate the acid-base balance (pH) of the blood.
Faster or slower breathing adjusts CO₂ levels, helping maintain pH within a narrow range.
Air moving through the larynx (voice box) causes the vocal cords to vibrate, producing sound.
This is essential for speech and other vocalizations.
Airborne molecules are detected by olfactory receptors in the nasal cavity, enabling the sense of smell.
This also contributes to taste and helps detect dangerous substances (like smoke or spoiled food).
The respiratory tract filters, warms, and humidifies incoming air.
Mucus and cilia trap and remove dust, pathogens, and other particulates, helping protect the body from infection and irritation.
The movement of air into (inhalation) and out of (exhalation) the lungs ensures continuous gas exchange.
Driven by the diaphragm and intercostal muscles.
The lungs are involved in converting angiotensin I to angiotensin II (a function of the pulmonary endothelium), which helps regulate blood pressure.
Lungs also help in the metabolism and clearance of various substances.
Let me know if you'd like a diagram or a more detailed explanation of any of these.