What is endoplasmic reticulm

Endoplasmic Reticulum (ER) is a complex network of tubular membranes present within the cytoplasm of the eukaryotic cell, transpiring either with a smooth surface and therefore called as the smooth endoplasmic reticulum or studded with ribosomes and hence called the rough endoplasmic reticulum which is involved in the transportation of materials. These membranes are continuous, joining with the outer membrane of the nuclear membrane . They occur in almost every type of eukaryotic cell except red blood cells and sperm cells. It has a number of jobs within the cell. Its functions are varied. Be its protein synthesis, folding, transport of cellular materials or transport of various proteins, specifically carrying them to the Golgi apparatus. It makes its presence known in all the mentioned areas.