What is produced as a byproduct of photosynthesis?

During photosynthesis, plants, algae, and some bacteria convert light energy into chemical energy, using carbon dioxide and water as raw materials. A major byproduct of this process is oxygen, which is released into the atmosphere. This occurs in the chloroplasts during the light-dependent reactions when water molecules are split (a process known as photolysis) to release electrons needed for the production of ATP and NADPH. The oxygen produced is essential for the survival of aerobic organisms, including humans, as it is used in cellular respiration. This pivotal role of oxygen in photosynthesis not only supports life on Earth but also contributes significantly to the planet's atmosphere.