Unit 1 - Topic 2 - Proteins - Section B - The synthesis and transport of proteins - Part II - Synthesis of membrane components Flashcards
What are synthesised in the ER
Lipids and proteins
What is the difference between rough and smooth ER
Rough ER (RER) has ribosomes on its cytosolic face while smooth ER (SER) lacks ribosomes.
Where are lipids synthesised
In the smooth endoplasmic reticulum (SER) and inserted into its membrane
Where does the synthesis of proteins begin
Cytosolic ribosomes
Where does the synthesis of cytosolic proteins complete
Completed in the cytosolic ribosome and these proteins remain in the cytosol
What do transmembrane proteins do
They carry a signal sequence, which halts translation and directs the ribosome synthesising the protein to dock with the ER, forming RER
What is a signal sequence
A short stretch of amino acids at one end of the polypeptide that determines the eventual location of a protein in a cell
When does translation continue
After docking, and the protein is inserted into the membrane of the ER
