The Nitrogen Cycle Is One of the Most Important and Complex

Multiple Choice

The nitrogen cycle is one of the most important and complex of the biogeochemical cycles. It is important because nitrogen:

A) is stored in sedimentary rock
B) is an essential part of biological molecules such as proteins and nucleic acids (DNA)
C) is the most toxic element to living organisms
D) dilutes the oxygen in the atmosphere causing respiratory problems
E) is a crucial part of the process of photosynthesis