Nitrogen N Atomic Number: 7 Atomic Weight: 14.007 _______________________________________________________________________________ Human Physiology: - Essential component of amino acids which are the building blocks of life Prevalence: - 78% of earth's atmosphere Source: - In plants, nitrogen fixing bacteria in roots is vital to converting nitrogen to usable form - Poisonous forms in car exhaust, zamboni machines, silos, welding fumes, fertilizers Deficiency: - Diarrhea - Wasting Excess: - Not toxic on its own