Which of the following does not cycle into the atmosphere?

a. the carbon cycle

b. the phosphorus cycle

c. the nitrogen cycle

d. the oxygen cycle

The answer is b. the phosphorus cycle. Phosphorus comes from the land and oceans and it is not present in the atmosphere. The reason for this is that phosphorus is not in the gaseous state, unlike oxygen, nitrogen, and carbon. Thus, phosphorus cycle into the lithosphere, hydrosphere, and biosphere, but not the atmosphere.