The gas essential for life and produced by plants is oxygen. Through the process of photosynthesis, plants convert carbon dioxide and sunlight into glucose and oxygen. This process occurs primarily in the chloroplasts of plant cells and is vital for sustaining life on Earth. Oxygen is released into the atmosphere as a byproduct, which animals and humans then inhale to survive. The balance of oxygen production by plants and consumption by animals is crucial to maintaining ecological harmony and supporting diverse life forms worldwide.