DENDROLOGY

Detailed explanation-1: -Scientists estimate that roughly half of the oxygen production on Earth comes from the ocean. The majority of this production is from oceanic plankton-drifting plants, algae, and some bacteria that can photosynthesize.

Detailed explanation-2: -During photosynthesis, plants take in carbon dioxide (CO2) and water (H2O) from the air and soil. Within the plant cell, the water is oxidized, meaning it loses electrons, while the carbon dioxide is reduced, meaning it gains electrons. This transforms the water into oxygen and the carbon dioxide into glucose.

Detailed explanation-3: -Answer and Explanation: The oxygen produced during photosynthesis comes from water.

Detailed explanation-4: -In photosynthesis, solar energy is harvested and converted to chemical energy in the form of glucose using water and carbon dioxide. Oxygen is released as a byproduct.

Detailed explanation-5: -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.