Endoplasmic Reticulum is an internal system which is formed by cell membrane .It extends from cell membrane to nuclear envelop. Membrane bound compartment which composed of Endoplasmic Reticulum are called CISTERNAE.
They are either tubular or flatted seat like in shape.
Endoplasmic Reticulum is prominent and abundant in secretary cells.
EX; Cells of glands like pancreas
There are two types of endoplasmic reticulums present in Eukaryotic cells
1. Smooth endoplasmic reticulum
2. Rough endoplasmic reticulum
Smooth Endoplasmic Reticulum
Cisternae are tubular shape .
Surface lacks of ribosomes, hence smooth.
Smooth endoplasmic reticulum occur connected to rough endoplasmic reticulum.
Smooth endoplasmic reticulum is abundant in liver cells and steroid secreting cells.
Ex; cells of ovaries
Testis
Functions of smooth endoplasmic reticulum
1.Synthesis of lipids
2.Detoxification of toxins,
smooth endoplasmic reticulum in liver cells detoxify alcohols, drugs and other toxic chemicals.
3.Storage of calcium
4.Provide support to cells
Rough Endoplasmic Reticulum
Cisternae are flatted seat like.
Surface contain a large number of ribosomes,hence rough.
Rough endoplasmic reticulum is usually connected to nuclear envelop.
Rough endoplasmic reticulum is abundant in protein and enzyme synthesizing cells .
