Respiratory anatomy; drawing shows right lung with upper, middle, and lower lobes; left lung with upper and lower lobes; and the trachea, bronchi, lymph nodes, and diaphragm. Inset shows bronchioles, alveoli, artery, and vein.

Anatomy of the respiratory system, showing the trachea and both lungs and their lobes and airways. Lymph nodes and the diaphragm are also shown. Oxygen is inhaled into the lungs and passes through the thin membranes of the alveoli and into the bloodstream (see inset).

From: Small Cell Lung Cancer Treatment (PDQ®)

Cover of PDQ Cancer Information Summaries
PDQ Cancer Information Summaries [Internet].
Bethesda (MD): National Cancer Institute (US); 2002-.

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