9. Genes and protein synthesis

• What is a genetic code

  A sequence that codes for the proteins
• What are the three important features of the genetic code

  Non overlapping - each base is part of only one triplet

  degenerate - amino acids can be coded for by more than one triplet

  universal - same in every organism
• What is ribosomal RNA

  With proteins it can make ribosomes.
• What is messenger RNA

  single linear strand that is formed after transcription. An amino acid is coded for by the triplet based codon On the mrna
• What is transfer rna

  Small molecule that is a single strand folded up. Stabilise the molecule

  one end of the chain attaches to an amino acid and the other attaches to the codon of mrna
• What are introns

  Does not code for a protein
• Where are introns found

  Between genes
• What happens to introns

  Spliced
• What is transcription

  Forms pre mrna
• Describe transcription

  Hydrogen bonds between dna strands break and one strand acts as a template. Free rna nucleotides complementary base pair. Bond together to form pre mrna. Introns are spliced
• Describe translation

  mRNA attaches to a ribosome. tRNA anticodons bind to the mRNA codons by complementary base pairing. tRNA carries a specific amino acid. the ribosome holds two tRNA molecules, a peptide bond forms between the amino acids. The tRNA molecules are released, and the ribosome moves along the mRNA.