Specialty Medical Coding Certification. 1  Hematology and Oncology â CHONCâ¢. 2  Internal Medicine â CIMCâ¢. 3  Interventional Radiology and Cardiovascular â CIRCCÂ®. 4  Obstetrics Gynecology â COBGCâ¢. 5  Ophthalmology â COPCâ¢. 6  Orthopaedic Surgery â COSCâ¢. 7  Otolaryngology â CENTCâ¢. 8  Pediatrics â CPEDCâ¢. FREE Practice Exam & Study Guide through Aug 31st.
Oxygen is a chemical element with symbol O and atomic number 8. It is a member of the chalcogen group on the periodic table and is a highly reactive nonmetallic element and oxidizing agent that readily forms compounds (notably oxides) with most elements. Photosynthesis releases oxygen, and respiration consumes oxygen.
The word oxygen comes from Greek words: oxus (acid) and gennan (generate). Oxygen comes to earth from all parts of the universe in meteorites. It is also found in minerals and plants that grow on the earth and other planets.