Endomembrane system - Endoplasmic Reticulum

Question 1

Describe Endoplasmic Reticulum

Answer 1

ER, is a network or reticulum of tiny tubular structures scattered into cytoplasm

Question 2

ER divides the intracellular space into how many compartments?

Answer 2

ER divides the intracellular space into two distinct compartments
a) luminal ( inside ER)
b) extra luminal (cytoplasm)

Question 3

Classification of ER based on the presence of ribosomes on their surface

Answer 3

Endoplasmic reticulum can be classified into
-Rough Endoplasmic Reticulum: ribosomes are present on their outer surface

-Smooth Endoplasmic Reticulum: in the absence of ribosomes they appear smooth and they are called smooth endoplasmic reticulum

Question 4

Functions of ER

Answer 4

RER is frequently observed in cells actively in protein synthesis and secretion, they are extensive and continous with outer membrane of nucleus

Question 5

Functions of SER

Answer 5

• The major synthesis site for lipid
• In animal cells lipid like steroidal hormones are synthesiz ed in SER