The essential element responsible for oxygen production through photosynthesis is chlorophyll, a pigment found in plants, algae, and some bacteria. During photosynthesis, chlorophyll captures sunlight, enabling these organisms to convert carbon dioxide and water into glucose and oxygen. This process not only provides energy for the plant but also releases oxygen as a byproduct, which is vital for the survival of aerobic organisms, including humans. The ability of chlorophyll to harness sunlight is fundamental to life's energy cycle on Earth.