Nitrogen cycle review: - Home - Woodland Hills School District

Nitrogen Cycle Worksheet. Introduction: All organisms need nitrogen to make DNA, RNA, and proteins, the building blocks of life. Although the Earth’s atmosphere is about 78% nitrogen, most of the nitrogen in the atmosphere occurs primarily in an inert form (N. 2) that few organisms can use; therefore, in order for plants and animals to be able to use nitrogen, N 2. gas must first be ... ................
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