QUESTION 7

1. Describe how atmospheric carbon dioxide levels fluctuate daily, seasonally, and geographically. Explain why such fluctuation occurs.

   Your response should be at least 75 words in length.

   QUESTION 8

   1. Describe the movement of an atom of nitrogen from the leaf of a plant, through the process of decomposition, and back into the root of another plant.

      Your response should be at least 200 words in length.