ABSTRACT
I. INTRODUCTION Many plant parts, including many flowers, fruits, and seeds, do not contain chlorophyll and are therefore not photosynthetically competent. Other plant parts, particularly underground roots, rhizomes, and tubers, are located on the plant in areas where light reception is insufficient to drive photosynthesis. In plant parts such as meristems, stems, and developing leaves, modification, incomplete development, or insufficient number of plastids also limits photosynthetic competence. Photosynthetic activity is therefore found to be largely confined to organs located in areas of maximal light interception and containing fully functional chloloplasts. In higher plants, these organs are represented by mature, fully expanded leaves.
