The network or membranes present in the cytoplasm for the transport of substances from the one part of the cell to another is known as endoplasmic reticulum.
Endoplasmic reticulum is of two types.
i) Rough endoplasmic reticulum and
ii) Smooth endoplasmic reticulum.
Endoplasmic reticulum having ribosomes on their surface is known as rough endoplasmic reticulum.
The rough endoplasmic reticulum is the sites of protein synthesis.
Ribosomes are absent in smooth endoplasmic reticulum and is involved in lipid synthesis.
One function of the endoplasmic reticulum is to serve as channels for the transport of materials within the cytoplasm.
It also function as a cytoplasmic framework providing a surface for some of the biochemical activities of the cell.
