they don't consist of chlorophyll which adds to the green colour of leaves as well as helps in trapping sunlight (in leaves)..........spores under leaves help in taking in air from atmosphere (also give out )........and roots basically transport water and important minerals from soil to leaves.
All these structures help in obtaining components necessary for photosynthesis BUT DO NOT UNDERGO PHOTOSYNTHESIS.........it is the leaves which do this.
so to conclude, roots just help in completing the required components necessary for photosynthesis but do not perform it.
HOPE IT HELPED !!!!!