Which of the following statements about biogeochemical cycling is correct?
A) The phosphorus cycle involves the recycling of atmospheric phosphorus.
B) The phosphorus cycle involves the weathering of rocks.
C) The carbon cycle is a localized cycle that primarily involves the burning of fossil fuels.
D) The carbon cycle has maintained a constant atmospheric concentration of CO₂ for the past million years.
E) The nitrogen cycle involves movement of diatomic nitrogen between the biotic and abiotic components of the ecosystem.

Question

Quizplus · Accepted Answer

The phosphorus cycle involves the weathering of rocks, which releases phosphorus into the soil and water where it can be taken up by plants and incorporated into the food chain. Atmospheric phosphorus is not a significant source of phosphorus in the biogeochemical cycle.

Answer: E
 The nitrogen cycle involves the movement of diatomic nitrogen (N₂) between the biotic and abiotic components of the ecosystem. Nitrogen fixation by certain bacteria converts N₂ into useable forms like ammonia and nitrates that can be taken up by plants, while denitrification by other bacteria returns N₂ to the atmosphere. This cycling of nitrogen is essential for the growth of plants and the functioning of ecosystems.

Which of the Following Statements About Biogeochemical Cycling Is Correct