Protein Synthesis

• TRANSCRIPTION

  1. The HYDROGEN BONDS between the COMPLEMENTARY BASES break and DNA uncoils, thus separating the two strands.
  2.  One of the DNA strands is used as a TEMPLATE to make the mRNA molecule. The template is called the ANTISENSE
  3. Free NUCLEOTIDES line up by complementary base pairing and ADJACENT NUCLEOTIDES are joined by PHOSPHODIESTER BONDS, thus forming a molecule of mRNA. This is CATALYSED by RNA polymerase
  4. mRNA then moves OUT of the NUCLEUS through a PORE and ATTACHES to a RIBOSOME in the CYTOPLASM which is the site of the next stage of protein synthesis
• Translation

  1. mRNA attaches to RIBOSOME

  2. tRNA binds to specific amino acids from cytoplasm based on anti-codon

  3. Complementary anticodons of tRNA bind to mRNA codons held by hydrogen bonds

  4. Ribosome joins amino acids attached to 2 tRNA molecules by peptide bond

  5. tRNA molecules detach from amino acids

  6. Process repeated until stop codon reached on mRNA