Translation

Question 1

Stage 1 Translation

Answer 1

The mRNA strand formed in the nucleus attaches to a ribosome in the cytoplasm. The mRNA is attached to the start codon (AUG), at the 3’ end of the strand

Question 2

Stage 2 Translation

Answer 2

Transfer RNA (tRNA) molecules contain a sequence of three bases called an anticodon. The tRNA molecule will bond with a complementary codon on the mRNA strand

Question 3

Stage 3 Translation

Answer 3

As the ribosome moves along the mRNA strand another tRNA moves in carrying the corresponding amino acid. The two amino acids are then joined together with a peptide bond by an enzyme

Question 4

Stage 4 Translation

Answer 4

Another tRNA molecule moves into the ribosome, adding another amino acid to the chain. The first tRNA molecule is released, and is free to collect another amino acid from the cytoplasm

Question 5

Stage 5 Translation

Answer 5

This process continues until a stop codon is reached on the mRNA strand. As there is not a corresponding tRNA for this sequence, the polypeptide is released. The polypeptide will then undergo post-transitional modifications before it is able to function

Question 6

Post Transitional Modifications

Answer 6

Removal of methionine, addition of functional groups, structural changes