What happens when the respiratory system functioning properly?
1. Gas Exchange: The primary function of the respiratory system is to facilitate gas exchange. During inhalation, fresh air is drawn into the lungs through the nose or mouth. Oxygen from the inhaled air diffuses across the thin walls of the alveoli (tiny air sacs in the lungs) into the bloodstream. Simultaneously, carbon dioxide, a waste product of cellular metabolism, diffuses from the bloodstream into the alveoli and is exhaled.
2. Oxygen Transport: Oxygen-rich blood is pumped by the heart to all tissues and organs in the body. Hemoglobin, a protein in red blood cells, binds to oxygen in the lungs and releases it in tissues where oxygen is needed for cellular respiration.
3. Carbon Dioxide Removal: Carbon dioxide, a waste product of cellular respiration, is transported back to the lungs by the bloodstream. In the alveoli, carbon dioxide diffuses from the bloodstream into the exhaled air.
4. Breathing Regulation: The respiratory system is regulated by the brain and responds to changes in the body's oxygen and carbon dioxide levels. The respiratory rate (the number of breaths per minute) and the depth of each breath are adjusted to maintain appropriate levels of these gases in the bloodstream.
5. Protection from Harmful Substances: The respiratory system serves as a filter for inhaled air. The nose and throat contain structures that help trap dust, pollen, and other particles, preventing them from reaching the lungs. Mucus produced in the respiratory tract also helps trap foreign particles and microorganisms.
6. Regulation of Acid-Base Balance: The respiratory system plays a role in maintaining the acid-base balance of the body by adjusting the rate and depth of breathing. Changes in breathing patterns can influence the levels of carbon dioxide in the bloodstream, which affects the pH of body fluids.
7. Voice Production: The respiratory system is essential for vocalization. The flow of air from the lungs passing through the larynx (voice box) causes the vocal cords to vibrate, producing sound. The resonant cavities in the face and throat further modify these sounds, allowing us to produce speech and other vocalizations.