Nucleic acids

• Base and sugar of a nucleotide bond by glycosidic bonds.
• Phosphate and sugar bond by an ester bond.
• Condensation polymerisation creates single stranded nucleotide chains
• Phosphodiester bonds hold nucleotides together
• Polynucleotides run anti parallel in order to from DNA double helix structure
• Hydrogen bonds between bases, 3 between C and G, 2 between A and T
• DNA replicates from 3 prime to 5 prime carbon bonds
• Semi conservative replication is where half of the DNA strand is replicated
• DNA replication

  • helicase breaks H bonds between bases and uncoils DNA helix
  • free floating nucleotides are sent to open nucleotides through complementary base pairing
  • polymerase bonds the new nucleotides and original nucleotides together through phosphodiester bonds to form H bonds between bases through condensation reaction
• Polymerase is an enzyme that bonds new nucleotides together and bases together in DNA replication
• Helicase is the enzyme that breaks the helix shape of DNA by breaking H bonds between bases to unravel DNA for replication
• Purines are bases with a double ring structure and are adenine and guanine
• Pyrimidines have a single ring structure and are thymine, cytosine and uracil
• RNA does not have the base thymine. It has uracil instead
• There are 3 types of RNA

  • rRNA- ribosome RNA that reads and codes for mRNA
  • mRNA- the messenger RNA of genetic information from nucleus to ribosomes
  • tRNA- involved in bringing amino acids together in translation of protein synthesis
• Phospodiester bonds between phosphate and carbon 4
• Phosphodiester bond