Endoplasmic Reticulum Flashcards
ER was discovered by
Porter and Thompson
ER term was given by
Porter
Define ER.
It s a network of membrane bound tubes and sheets scattered in the cytoplasm.
What is ER connected to?
At one side, it is connected to the nuclear membrane ( outer membrane of nucleus).
The other end is present near PM ( may or may not be connected with PM)
What are the three forms of ER
- Cisternae
- Tubules
- Vesicles
Which form is ER is
Long, flattened sac like structure and actively involved in protein synthesis?
Cisternae
Eg: in brain and pancreas
Which form of ER is
Tube like structure, which could be branched or unbranched and involved in synthesis of lipid and sterol?
Tubules
Which form of ER is membrane bound sac like structure?
Vesicles
Eg : in spermatocytes
What is luminal compartment?
Space present inside ER
What is extra luminal compartment?
Space present outside ER
What are the types of ER
- Rough Endoplasmic Reticulum
- Smooth Endoplasmic Reticulum
Why is RER called granular ER?
Because of presence of Ribosomes
Larger subunit in the 80s ribosome is connected with the help of
Ribophorin
Which type of ER is proximal to nuclear membrane?
RER
Which type of ER is distal to nuclear membrane
SER
Which ER is involved in synthesis of protein?
Rough ER
What are secretory proteins?
They are transported out of cell.
What are membrane proteins?
The proteins that are used inside the cell.
Which ER is involved in synthesis of lipids and sterol?
Smooth ER.
Which ER is involved in detoxification of foreign compounds?
Smooth ER
What are foreign compounds called as?
Xenobiotics
For eg:- drugs, medicines etc.
What does cytochrome P450 do?
It converts lipid solubles into water solubles.
How is contraction of muscles by SER caused?
By release and upstake of calcium ions
What is involved in the synthesis of sphaerosomes and glyoxysomes?
Smooth ER
