Which natural environment takes in more carbon dioxide through photosynthesis than it produces through respiration?

• A. Carbon sink
• B. Carbon store
• C. Bioremediation
• D. Biotic

Answer: (A)

Think about the balance between taking in CO2 through photosynthesis and releasing it through respiration. In a carbon sink, the amount of CO2 removed from the atmosphere by photosynthesis and stored in biomass, soils, or sediments exceeds the CO2 released back by respiration and decay. This means the environment net absorbs CO2 over time, so atmospheric CO2 decreases.

A carbon store is simply a place where carbon is kept, but it doesn’t necessarily imply ongoing net uptake. Bioremediation uses living organisms to clean pollutants, which isn’t about carbon balance. Biotic just refers to living things, not the carbon exchange process.

So, the natural environment that takes in more CO2 through photosynthesis than it produces through respiration is the carbon sink.