→ The human respiratory system is responsible for the exchange of gases, primarily oxygen and carbon dioxide, enabling us to breathe and sustain life.
→ The process begins with air entering through the nostrils, where tiny hairs and mucus trap dust and dirt particles.
→ The air then passes through the nasal passages, which warm and moisten it before it enters the windpipe (trachea).
→ The trachea divides into two bronchi, one for each lung. Inside the lungs, the bronchi further branch into smaller and finer tubes called bronchioles, which end in tiny air sacs known as alveoli.
→ These alveoli are surrounded by a network of blood vessels.
→ Oxygen from the inhaled air diffuses across the thin walls of the alveoli into the blood, while carbon dioxide from the blood moves into the alveoli to be exhaled.
→ The diaphragm, a dome-shaped muscle below the lungs, and the rib cage play crucial roles in breathing. During inhalation, the diaphragm contracts and moves downward, while the rib cage expands, increasing the chest volume and allowing air to rush into the lungs.
→ During exhalation, the diaphragm relaxes and moves upward, while the rib cage contracts, decreasing the chest volume and forcing air out of the lungs.
→ This continuous exchange of gases ensures that the body receives the oxygen it needs and eliminates carbon dioxide, a waste product of cellular activities.