What do plants make during photosynthesis?

During photosynthesis, plants absorb sunlight and use that energy to convert water and carbon dioxide into glucose, a sugar that serves as the plant's food and energy source, releasing oxygen as a byproduct in the process. This single reaction, occurring in chloroplasts within plant cells, is responsible for producing both the food energy that supports most food chains on Earth and the oxygen that most animals, including humans, depend on to breathe.

Producing only carbon dioxide would be backwards, since carbon dioxide is actually an input that plants absorb, not a product they generate during this process. Producing salt and water doesn't reflect what photosynthesis actually creates; water is consumed as a raw material, and salt plays no role in the reaction at all.

Because photosynthesis removes carbon dioxide from the atmosphere and locks that carbon into plant tissue, forests and oceans full of photosynthesizing organisms act as major natural carbon sinks, which is part of why deforestation and ocean health are so closely tied to conversations about climate change.