Which cycle involves the exchange of carbon among the atmosphere, oceans, soil, and living organisms?

Which cycle involves the exchange of carbon among the atmosphere, oceans, soil, and living organisms?

• A. Carbon Cycle
• B. Disphotic Zone
• C. Biogeochemical Cycle
• D. Diffusion

Answer: (A)

The main idea here is how carbon moves and is stored among different parts of the environment: the atmosphere, oceans, soils, and living organisms. The carbon cycle describes these transfers and stores, including processes like photosynthesis pulling CO2 from the air into plants, respiration returning CO2 to air and water, carbon exchange between seawater and the atmosphere, uptake of carbon by phytoplankton, and the burial of carbon in soils and sediments. It also includes weathering of rocks that releases CO2, along with long-term storage in fossil fuels and sediments. Because the question is asking about the cycle specifically involving carbon among those reservoirs, the carbon cycle is the best fit. A biogeochemical cycle is a broader term covering cycles of many elements, not just carbon. The disphotic zone is a depth region in the ocean, and diffusion is a transport process, not a cycle.

The main idea here is how carbon moves and is stored among different parts of the environment: the atmosphere, oceans, soils, and living organisms. The carbon cycle describes these transfers and stores, including processes like photosynthesis pulling CO2 from the air into plants, respiration returning CO2 to air and water, carbon exchange between seawater and the atmosphere, uptake of carbon by phytoplankton, and the burial of carbon in soils and sediments. It also includes weathering of rocks that releases CO2, along with long-term storage in fossil fuels and sediments. Because the question is asking about the cycle specifically involving carbon among those reservoirs, the carbon cycle is the best fit. A biogeochemical cycle is a broader term covering cycles of many elements, not just carbon. The disphotic zone is a depth region in the ocean, and diffusion is a transport process, not a cycle.