Biogeochemical Cycles: The Key to Nutrient Circulation in the Biosphere

How do biogeochemical cycles contribute to the circulation of nutrients in the biosphere?

A. Human activity has no effect on elements, chemical compounds, and another form of matter.

B. Living organisms are not limited by any one nutrient.

C. Nutrients are circulated throughout the biosphere.

D. Many nutrients do not reach toxic concentrations in the biosphere.

Answer:

The correct answer is C. Nutrients are circulated throughout the biosphere.

Biogeochemical cycles, including the carbon, hydrogen, oxygen, phosphorus, sulphur, nitrogen, and water cycles, play a crucial role in the circulation of nutrients in the biosphere. These cycles involve various processes where elements and compounds are exchanged between the living organisms, atmosphere, water bodies, and the Earth's crust. As these cycles are repeated over time, nutrients like carbon, nitrogen, phosphorus, and others are continuously moved and recycled within the ecosystem.

For example, in the nitrogen cycle, nitrogen is converted into different forms by bacteria, plants, and other organisms, making it available for various organisms to use. Similarly, the carbon cycle involves the movement of carbon through photosynthesis, respiration, decomposition, and other processes, ensuring that carbon compounds are constantly exchanged between different components of the biosphere.

Overall, the biogeochemical cycles ensure that nutrients are not only available for organisms to survive and grow but also prevent the accumulation of toxic concentrations of elements in the biosphere. Without these cycles, the balance of nutrients in ecosystems would be disrupted, leading to significant impacts on the overall health and functioning of the biosphere.