Protein Synthesis

•  what describes transcription? 

  The copying of a single gene of DNA, to mRNA
• Where does transcription take place?

  Nucleus 
• Why does a gene of DNA have to be copied to mRNA (transcription)?

  DNA is too large to leave the nucleus 
• How is mRNA different to DNA?

  mRNA is shorter than DNA

  mRNA is single stranded, but DNA is double stranded 
• Once the mRNA leaves the nucleus and enters the cytoplasm, which sub-cellular structure (organelle) does it go to?


  Ribosome 
• describe translation? 

  The combination of amino acids to form a polypeptide
• How many bases are needed to code for one amino acid?

  3

  Each set of three bases is called a triplet, or a codon, and codes for one amino acid.
• What is the function of a ribosome?

  To assemble proteins from amino acids
• A chain of amino acids is called a

  Polypeptide 
• Different sequences of amino acids within a polypeptide will fold up into different shapes, and so form different proteins.