The process begins at the phragmoplast, a barrel-shaped region at the former sits of the spindle equator, where microtubules remain and the vesicles cluster, possibly oriented by the microtubules.

• 这个过程在成膜体中开始，成膜体是残留的纺锤体微管在细胞赤道面中央密集，微管以平行方式排列形成的圆柱状结构。