Question: How do trees make oxygen

Duncan Smallman answered on 25 Mar 2026:

Trees, like other plants and organisms like seaweed and blue-green algae (or cyanobacteria) all photosynthesise. This is the process of taking carbon dioxide and using sunlight to break it down to make sugars (energy) they can use in their cells. Photosynthesis occurs in special structures called chloroplasts contained within the cells. The chlorophyll in the cholorplasts help give the leaves a green colour.