The amyloplast envelope began to degrade after amyloplast was full of starch granules.Degraded membrane fragments surrounded cytoplasmic matrix to form ring membrane structure.

• 淀粉体被淀粉粒充实后，淀粉体被膜开始降解，降解的被膜片段发生卷曲包裹细胞质基质形成环形被膜结构。