Endoplasmic Reticulum
. () Endomembrane system cytoplasmic vacules system cytoplasmic vacules net :
1- Nuclear envelope.
2- Golgi complex.
3- Endoplasmic reticulum .
Porter 1953.
. . :
1- (Cisternae) lamellar form
(40-50) stacks RER .
2- Vesicular form
(25-500) SER.
3- Tubular form
(50-190) SER Dynamic .
Fluid Mosaic Model .

Types of endoplasmic reticulum
:
1- : Rough endoplasmic reticulum
(Granular) ( Palade 1955) 60% 40% RNA 100-150 Subunits Large subunit small subunit Strand RNA mRNA Polysomes Protein Synthesis. RNA .

2- Agrnular or smooth endoplasmic reticulum
Spermatocyte
adipose cells Interstitial cells . Sarcoplasmic reticulum. 25-500 50-100 .

Ultrastructure of endoplasmic reticulum
Cisternae (50-60) Fluid Mosaic Model membrane unit . Palade 1956 Plasma cells goblet cells Weibel 1969 (1) (10)2 RER.

Glycosomes
SER RER Tubular form Glycosomes (50-200) EM .

Functions of endoplasmic reticulum
1- : .
2- : 112 / Hypertonic Hypotonic Permeases.
3- : Serum Protein Tropocollagen Secretion Granules Polysomes .
4- : .
5- : Sarcoplasmic Reticulum . .
6- .
7- .
8- .

Origin of Endoplasmic Reticulum
Gay 1956 bleds Seikevitz Palade 1960 RER SER .