Task: Text Categorization
Input (English): One important metabolic pathway named for a compound containing this element generates ornithine and its namesake substance, urea. Pyrimidine and purine bases, such as adenine and thymine, are often given a name that reflects their containing this element. Bacteria fix this element by forming ammonia. For 10 points, name this element found in the amino group of amino acids, whose diatomic form is an inert gas.
Output (English): Science