human respiratory system: Quick Facts

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Medical illustration of the human chest showing the lungs, diaphragm, ribs, trachea, bronchus, and bronchioles, with one lung cut away to reveal internal structures.

Medical illustration showing a sagittal section of the human head focused on the nasal cavity, with labeled parts including the frontal and sphenoid sinuses, ethmoid bone, conchae, nasal vestibule, oral cavity, soft palate, anterior nasal spine, and tongue.

A labeled medical illustration shows a sagittal section of the pharynx, highlighting anatomical features such as the tonsils, palate, tongue, epiglottis, and related muscles. An inset diagram identifies the nasal, oral, and laryngeal regions of the pharynx in color.

Educational diagram showing the human voice-producing apparatus, including a side view of the head and neck with labeled tongue, larynx, vocal cords, and trachea, plus a top-down view of the vocal cords during inhalation and sound production. Labels explain the roles of resonators, vocal cord positioning, and cartilage structures in speech.

Medical image showing a detailed view of healthy human lungs, highlighting the trachea, bronchi, and branching bronchioles within the chest.

diaphragm; breathing

Diagram of the hemoglobin tetramer showing two alpha and two beta subunits, each in a different color, with four heme groups labeled, each containing a central iron atom for oxygen binding.

A scuba diver swims underwater wearing a wetsuit and air tank, with a stream of bubbles rising toward the surface.

diagram of the human respiratory system

Passage of air through the respiratory tract explained

A swimmer wearing goggles and a swim cap turns their head to breathe while swimming in open water, emphasizing the act of breathing during exercise.

Why sleep is so important

Understanding the mechanics of human respiration

How do red blood cells circulate oxygen throughout the human body?

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Topics

breathing gas exchange lung trachea larynx pharynx nose diaphragm Vocalization respiratory syncytial virus infection human nervous system human eye human digestive system renal system human cardiovascular system human endocrine system human sensory reception human reproductive system human skin human skeleton

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