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Biology at Clermont College: The Respiratory System
What do you know about the respiratory system? This site gives a detailed description of this integral human body system. Don't miss out.
Wikimedia
Wikipedia: Chalcogen
An informative article from the Wikipedia encyclopedia about Group 16 from the Periodic Table (also known as the Chalcogens). It gives information about their compounds and on the oxidation numbers of the elements.
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Reynolds Office of Health and Nutrition: Oxygen
This site contains an essay that discusses the significance of oxygen and why it is vital to humans.
Curated OER
Science Kids: Science Images: Oxygen
This hazardous materials sign is to warn of potentially dangerous oxygen in the area.