The primary purpose of the respiratory system is gas exchange to help move oxygen throughout the body and clean out waste gases like carbon dioxide.

Museum-quality posters made on thick and durable matte paper.

• Paper thickness: 10.3 mil
• Paper weight: 5.57 oz/y² (189 g/m²)
• Giclée printing quality
• Opacity: 94%

Illustrations By:
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Sources:
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