Problem 22
Describe how each of the following is involved in the nitrogen cycle: atmospheric nitrogen, nitrogen-fixing bacteria, nitrifying bacteria, denitrifying bacteria, producer, protein, consumer, and decomposer.
Problem 23
List three ways humans have altered the nitrogen cycle.
Problem 24
Describe how each of the following is involved in the phosphorus cycle: phosphorus in rock, producer, consumer, animal waste, respiration, and decomposer.
