Ribosomes Flashcards
(12 cards)
Where an ribosome be found in the cell?
On ER or free floating in the cell.
How many binding sites does a ribosome, how many are for mRNA and how many are for tRNA
There aere 4 binding sites. 1 for mRNA and 3 for tRNA
Where is the mRNA binding site located?
small subunit of the ribosome.
What does the A site do?
accept the aminoacyl-tRNA
What does the P site do?
accepts the peptidyl tRNA. It is where the growing polypeptide chain is found.
What is the E site?
This is the exit site that facilitates dissociation of empty tRNA.
Describe a prokaryotic ribosome.
70S ribosome made up of a 50S large subunit and a 30S small subunit.
Describe a eukaryotic ribosome
80S ribosome made up of a 60S large subunit and a 40S subunit.
What is a polyribosome?
a series of ribosomes that all translate 1 mRNA molecule at the same time to increase translation rate.
What is co-translational folding?
The acquisition of the secondary and teritiary structure of the polypeptide as it emerges from the ribosome.
What terminal of the polypeptide folds first and what happens while it is folding?
The N-terminal folds first while the C terminal is synthesised and follows in folding.
True or False. When the protein is released from the ribosome it is in its final conformation.
False.
