There is nothing specific about green. Chlorophyll A and Chlorophyll B have different absorption spectrums. Depending on the specific combination of those two, the plants can appear in a different colours.
There are other pigments that cannot photosynthesise on their own, but can pass the energy to chlorophyll to react, as well. So while green usually means photosynthesis, absence of green does not mean absence thereof.
https://en.wikipedia.org/wiki/Chlorophyll#/media/File:Chloro...
There are other pigments that cannot photosynthesise on their own, but can pass the energy to chlorophyll to react, as well. So while green usually means photosynthesis, absence of green does not mean absence thereof.
https://ucmp.berkeley.edu/glossary/gloss3/pigments.html