3.RNA and protein synthesis

• What is the first stage of protein synthesis?

  DNA is first copied into mRNA
• Protein (polypeptide) synthesis:

  • production of proteins (polypeptide) from DNA
  • involves: Transcription- DNA is copied to mRNA. Translation- mRNA is used to synthesis protein within ribosome
• RNA:

  • single polynucleotide strand
  • Contains Uracil instead of thymine
  • nucleotides contain ribose
  • RNA is much shorter than DNA
• mRNA:

  • Made during transcription in nucleus
  • Carries genetic code from DNA to ribosomes
  • Single polynucleotide strand
  • 3 adjacent bases known as codon/triplet
• tRNA:

  • Important in translation
  • Carries amino acids to ribosomes to make polypeptide
• tRNA structure:

  • tRNA single polynucleotide folded into clover shape
  • Contains hydrogen bonds between specific pairs which holds shape together
  • Contains anticodon (3 bases) at one end and amino acid binding site on other end