Why is photosynthesis green

Why are plants green?

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Hannah (9) from Oerlikon ZH


Chlorophyll - also called leaf green - is a natural dye that plants need to carry out photosynthesis. It absorbs all other color components from sunlight, except for green, which is reflected and therefore makes plants appear green. Red leaves (e.g. copper beeches) also contain chlorophyll, but also other dyes, so-called anthocyanins, which mask the green color. Photosynthesis uses sunlight to turn carbon dioxide and water into essential sugars.

In the spring, as the sunlight increases, chlorophyll is produced.
With the decreasing sunlight in autumn, the chlorophyll is broken down.
The leaves of the trees then appear colorful, because other dyes and also degradation products become more visible.

The green part is reflected (mirrored) from the spectral light of the sun.


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