ABSTRACT
Starch is found in all organs of most higher plants including seeds, stems, leaves, roots, fruits, and pollen. As the principal storage carbohydrate of plants, starch is stored as insoluble granules. Starch in higher plants is found in cellular organelles, the plastids. However, starch granules in the red algae are found outside the chloroplasts while starch granules of green algae are formed within the chloroplast. The starch from red algae contains only amylopectin or a polysaccharide intermediate to amylopectin and the highly branched glycogens. Three types of information are important: the cellular compartmentation of starch metabolism, the enzymatic reactions and points and reactions with regulatory properties. Starch biosynthesis in higher plants occurs in plastids. The general consensus is that starch synthesis is compartmented in amyloplasts in storage tissues in spite of the paucity of evidence.
