steps in translation: elongation

Question 1

elongation

Answer 1

amino acids are brought into the ribosome to elongate the polypeptide then the ribosome is translocated to a new codon

Question 2

1. A (aka acceptor) site is filled

Answer 2

aminoacyl tRNAs (tRNA + amino acid) are brought to the A site of the ribsome (specific amino acid selected by complementary tRNA anticodon–mRNA codon binding) this is aided by protein elongation factors (EFs)

Question 3

2. Transpeptidation

Answer 3

the amino acids in the P site join the new amino acid in the A site via formation of a peptide bond between aa’s

Question 4

3. translocation

Answer 4

movement of the
ribosome along the mRNA occurs to
move a new codon into the A site

• What was in the A site moves to
  P site
• What was in the P site moves to
  the E site (aka exit)
• The A site will be ‘emptied’ so a
  new aminoacyl tRNA can enter it
• The uncharged tRNA in the E site
  dissociates from the ribosome
  completely