Plants contribute to the oxygen supply through the process of photosynthesis. During photosynthesis, plants take in carbon dioxide from the air and water from the soil. Using sunlight as an energy source, they convert these elements into oxygen and glucose. This oxygen is released into the atmosphere as a byproduct, which humans and other organisms then breathe in to survive. In fact, it is estimated that about half of the oxygen we breathe comes from plants through this process.
