Photosynthetic Orchid Roots  

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Orchid growing on a tree trunk in the dry forest of Puerto Rico. Note the extent of the root system and its green color. If you look carefully you can see the dry flowering stems which rise above the crick of the tree.

Closer view of Puerto Rican orchid which has photosynthetic roots. Locate the flowering stems. The bright green structure near the center is a new root!

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Center of the Puerto Rican Orchid with photosynthetic roots.

No vegetative shoots or leaves are visible.

Locate the withered flowering stem which is oriented towards 11:00.

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New green root tips near the center of the plant. Note the presence of a Velamen.

It is fairly obvious that the roots are the photosynthetic organ for these plants.

What features of the Velamen contribute to this phenomenon?

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