intracellular造句
        The sarcoplasmic reticulum is a system of 
intracellular membranes.
肌浆网属于细胞内膜系统.
In order to fuse, 
intracellular vesicles have to move within the cell.
为了融合, 细胞内的囊泡必须在细胞内运动.
The reactions may be extracellular or 
intracellular.
这些反应可以发生在细胞外,也可以发生在细胞内.