protein synthesis

• transcription is taking a single gene and copying it into mRNA, which is a single stranded molecule
• translation is using mRNA to create a protein
• DNA needs to leave the nucleus to get to the ribosomes so it is copied into smaller, single stranded molecules called mRNA
• mRNA is a copy of a single gene
• mRNA is only a single strand
• mRNA contains the base uracil (U) instead of thymine (T)
• U in mRNA joins to A in DNA
• during transcription, only a small part of DNA is ever exposed because as the RNA polymerase moves along, the strands close either side

  
• in translation, each group of 3 bases (a codon) codes for a specific amino acid
• translation involves amino acids being created by a ribosome which detaches and the amino acid chain folds up into a protein
• a polypeptide is a chain of amino acids