Respiratory System Basics
The respiratory system performs four key processes to keep you alive. First, pulmonary ventilation moves air in and out of your lungs. Then external respiration exchanges gases between your lungs and blood. Your blood handles transport of respiratory gases throughout your body. Finally, internal respiration exchanges gases between your blood and tissues.
Your respiratory system consists of conducting and respiratory zones. The conducting zone includes structures that air travels through—nose, nasal cavity, pharynx, larynx, trachea, and bronchi. The respiratory zone contains microscopic structures (respiratory bronchioles, alveolar ducts, and alveoli) where actual gas exchange occurs.
The nose serves multiple important functions beyond breathing. It moistens and warms incoming air, filters out foreign particles, enhances speech through resonance, and houses smell receptors. The external nose combines bone and cartilage structures, while the internal nasal cavity performs critical air conditioning.
Did you know? The nasal cavity doesn't just filter air—it contains special cells that produce antimicrobial substances like lysozyme and defensins that help destroy bacteria before they can enter your lungs!
