Biology / Unit 6 Bio 1285 short lesson, about 20 seconds
The Ribosome's A, P, and E Sites
Captions available
The idea
An assembled ribosome has three tRNA sites: A accepts an incoming tRNA, P holds the growing peptide, and E releases a used tRNA.
In practice
A charged tRNA enters site A, its amino acid is added to the chain at site P, and the emptied tRNA exits site E.
Where people slip
These sites are fixed positions in one ribosome, not three ribosomes acting on different tRNAs.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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