Question

which of these statements is true about biogeochemical cycles? a) in biogeochemical cycles, nutrients are not synthesized anew but are recycled in the biosphere b) in biogeochemical cycles, nutrients are not recycled in the biosphere but are synthesized anew c) in biogeochemical cycles, nutrients are not recycled in the biosphere but are depleted.

Answer 1

The answer is a) in biogeochemical cycles, nutrients are not synthesized anew but are recycled in the biosphere.

Biogeochemical cycles are pathways by which chemical substances move through biosphere and geosphere (lithosphere), as well as atmosphere and hydrosphere. In these cycles nutrients are recycled, they are not lost. Let's take for example a carbon cycle:

:- Carbon is released into the atmosphere as carbon dioxide from respiration.

- Producers (plants) absorb carbon dioxide and make carbohydrates in photosynthesis.

- Consumers (animals) eat producers and intake carbohydrates.

- After the death of both producers and consumers, decomposers (such as Actinobacteria, or other bacteria or fungi) eat that dead organisms and carbon are released into the environment.

So, carbon is not synthesized anew, but it is recycled.