What is the role of algae in the carbon cycle?

Algae play a crucial role in the carbon cycle by acting as primary producers that absorb carbon dioxide (CO2) from the atmosphere during photosynthesis. Through this process, they convert CO2 into organic matter, which forms the basis of the aquatic food web. Additionally, when algae die, they can sink to the ocean floor, effectively sequestering carbon in sediments for long periods, thus helping to regulate atmospheric CO2 levels and mitigate climate change.