Potato starch. Coloured scanning electron micrograph of starch grains isolated from the cells of a potato, Solanum tuberosum. The stored starch grains are called amyloplasts. Starch is synthesised from sucrose, a sugar formed in the leaves during photosynthesis and transported to the tuber (potato) through the phloem (vascular tissue). It is used as a store of energy for the later development of buds on the surface of the potato. Starch is an important food resource for humans, hence the potato's popularity as a crop. Magnification: x240 at 5x7cm size. x640 at 8x6ins