part of amyloplast amyloplast starch grain amyloplast starch granule cellular_component Plant storage body for amylose and amylopectin, 1-100um in diameter, and located in amyloplasts. Also contains small amounts of enzymes, amino acids, lipids and nucleic acids. The shape of the grain varies widely amongst species, but is often spherical or disk-shaped. GO:0009568 starch grain