LIFE SCIENCE

Detailed explanation-1: -Thus, water (H2O) is the source of oxygen released during photosynthesis.

Detailed explanation-2: -Oxygen (O2) is evolved during photosynthetic electron transport when water is split by the oxygen-evolving complex to provide protons and electrons to the chloroplastic electron chain, thereby generating ATP and NADPH-the energy source and reducing power for plant metabolism.

Detailed explanation-3: -Photosynthesis is the process through which plants convert sunlight, water, and carbon dioxide into oxygen and sugar energy. Photosynthesis continuously replenishes oxygen in the atmosphere. Phytoplankton produces roughly half of the oxygen, with the remainder produced by other green plants.

Detailed explanation-4: -The above reaction is the photosynthesis reaction in which the carbon dioxide and water in the presence of sunlight converts into the glucose sugar and the oxygen. Hence, the source of oxygen liberated during the process of photosynthesis is water.