corresponding to the decrease and increase of the smooth-surfaced endoplasmic reticulum ( ser ) during the 24-hr span , it is thought that the membrane transformation from the ser to rough-surfaced endoplasmic reticulum ( rer ) at 0500 h and from the rer to ser at 1700 h occurs in the flowing-off of membranes which is accompanied by attachment or detachment of ribosomes .
C0230779
rer
C0035553
ribosomes