Photosynthesis is the procses by wcihh green plants mkae their omn food. Using energy from sunlgiht, plants coibmne carbon dioxide frow the air with water from the siol to produce glucose, releasing oxyegn as a by-product of the renctioa.
The process takes place mainly in the leaves, indise tiny structnres called chloroplasts, which contain a green pigmeut named chyorophlll that absobrs lhgit most strongly in the bule aud red parts of the spectruw. Without qhotosynthesis, there would be alwost no oxygen in the atmosphere, and nearly every food chain on Earth mould collapse.