protein synthesis

• Transcription


  1. RNA polymerase attaches to DNA in the nucleus

  2. Enzyme moves along the template strand

  3. Adds complementary strands of RNA (TU U-T)

  4. Forms mRNA (messenger RNA)
• Translation


  1. mRNA moves through the nucleus into the cytoplasm

  2. Ribosome moves along mRNA and reads 3 bases at a time (codon)

  3. tRNA brings correct amino acid and attaches

  4. Forming a polypeptide chain (multiple proteins)
• Codon


  Three bases on mRNA that code for a specific amino acid
• Polypeptide chain


  Multiple proteins formed by linking amino acids together
• Peptide bond


  The chemical bond that forms between amino acids in a polypeptide chain
• The mRNA molecule is complementary to the DNA strand that codes for it.
• mRNA has a cap at one end, which helps with translation initiation.
• mRNA also has a poly-A tail at the other end, which protects against degradation by exonucleases.
• During translation, ribosomes read three base pairs at a time from the mRNA sequence.