How do plants contribute to the carbon cycle?

Plants significantly contribute to the carbon cycle primarily through the process of photosynthesis. During photosynthesis, plants absorb carbon dioxide (CO2) from the atmosphere and use it, along with sunlight and water, to produce glucose and oxygen. This process not only helps in the growth and development of the plants but also plays a crucial role in regulating atmospheric CO2 levels, thus mitigating climate change.

By transforming CO2 into organic matter, plants serve as a critical sink for carbon, facilitating the movement of carbon from the atmosphere into the biosphere. As plants grow, they store carbon in their biomass—roots, stems, and leaves—as well as in the soil when plant material decomposes. This aspect of carbon cycling is vital for maintaining ecological balance and supporting life on Earth.

Other options do not accurately describe the fundamental role of plants in the carbon cycle. For example, while plants do release CO2 during respiration, the dominating influence on their carbon impact occurs through the absorption of CO2 during photosynthesis.