Question

if an atom of nitrogen is not in a living organism, where is it?
thrown away in a landfill on the surface of the earth
not in existence anywhere else in the universe
in the nonliving portion of the environment
stored deep beneath the earths surface in its core

Explanation:

Nitrogen atoms cycle between living organisms and the non - living environment. If not in a living organism, they are in the non - living part of the environment. Landfills are a small part of the non - living environment. Nitrogen is abundant in the universe (e.g., in stars during formation). The Earth's core has very little nitrogen compared to the atmosphere and other non - living environmental components.

Answer:

in the nonliving portion of the environment