Plants are green because they reflect green light.
Here's a more detailed explanation:
Plants contain pigments, most notably chlorophyll, that absorb light in specific regions of the visible spectrum. This absorption is how plants capture the energy from sunlight needed for photosynthesis, the process by which they convert light energy into chemical energy (sugars).
How Light Absorption Works
Chlorophyll most effectively absorbs light in the red and blue regions of the spectrum. However, it's less efficient at absorbing green light.
| Light Color | Absorption by Chlorophyll |
|---|---|
| Red | High |
| Blue | High |
| Green | Low |
Because chlorophyll doesn't absorb green light efficiently, this portion of the light spectrum is reflected back. This reflected green light is what our eyes perceive, giving plants their characteristic green color. The reference provided states that plants absorb about 90% of green light photons, reflecting the remaining 10%. If plants absorbed all colors equally, including green, they would appear black.
In summary, the green color of plants is not due to them using green light for photosynthesis, but rather to the fact that they reflect it.
