mRNA

• Messenger RNA (mRNA)
• - Made by transcription in the nucleus
• Acts as a template for translation in the cytoplasm
• - Sequence of bases on RNA determines sequence of amino acids in polypeptide chain
• - Straight chain molecule
• Sequence of bases on RNA determined by sequence of bases on DNA
• Triplet code = codon
• - Chemically unstable
• So breaks down after a few days
• Messenger RNA (mRNA)

  • Made by transcription in the nucleus
  • Acts as a template for translation in the cytoplasm
  • Sequence of bases on RNA determines sequence of amino acids in polypeptide chain
  • Straight chain molecule
  • Sequence of bases on RNA determined by sequence of bases on DNATriplet code = codon
  • Chemically unstable
  • So breaks down after a few days

  
• Compare structures of tRNA and mRNA ?

  tRNA: Cloverleaf structure with anticodon

  carries amino acids to ribosomes during translation. mRNA: Single-stranded

  carries genetic information from DNA to ribosomes for protein synthesis.Similarities / differences between structure of mRNA and tRNA molecules

  Similarities- Both single polynucleotide strand

  Differences- mRNA single helix / straight, whereas tRNA folded into clover shape

  • mRNA is a longer, variable length, whereas tRNA is shorterm. contains no paired bases or hydrogen bonds, whereas tRNA has some paired bases and hydrogen bonds