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Which organs make up the human respiratory system?

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Illustration showing different animals and their respiratory organs: a spider with book lungs, a chicken with lungs, a sponge with labeled inflow and outflow pores, a fish with gills, and a caterpillar with spiracles. — Respiratory system Different methods of respiration in animals.

The human respiratory system is a complex network of structures designed to facilitate gas exchange. It is categorized into upper and lower airway systems, supported by essential muscles and other organ systems.1

Upper Airway System

The upper airways include the nose, the paranasal sinuses, the pharynx, and the oral cavity.1

Lower Airway System

The lower airways consist of the larynx, the trachea, the stem bronchi, and the internal structures of the lungs, including intrapulmonary bronchi, bronchioles, and alveolar ducts.12

Supporting Structures

Respiration relies on the collaboration of other systems:
* Musculature: The diaphragm and intercostal muscles generate the pumping action required for breathing.12
* Thoracic Cage: The ribs and thoracic vertebrae protect the lungs and facilitate chest expansion.1
* Circulatory System: The heart and blood vessels are mandatory for transporting gases throughout the body.1