DNA

• A nucleotide is a monomer that joins together to make the polymer of DNA.
• What is a nucleotide?

  A monomer that joins together to make the polymer DNA.
• What polymer do nucleotides join together to make?

  Polynucleotide
• What monomer makes up DNA?

  Nucleotides
• Nucleic acids are made up of basic units called nucleotides, each of which contain a phosphate group, sugar and a nitrogenous base.
• What makes up a nucleotide?

  A phosphate group, sugar and a nitrogenous base
• Nucleotides bind together through condensation reactions between the phosphate group of one and a carbon of the pentose sugar of the other. This is called a phosphodiester bond.
• What is the covalent bond between nucleotides called?

  A phosphodiester bond
• What reaction forms phosphodiester bonds?

  Condensation reactions
• What reaction breaks down phosphodiester bonds?

  Hydrolysis reaction.
• What is the bond between the sugar and base of a nucleotide called?

  A glycosidic bond
• What is the bond called between a phosphate and a sugar group on a nucleotide called?

  Phosphodiester bond
• What reaction forms a glycosidic bond?

  A condensation reaction
• What is released during a condensation reaction?

  One molecule of water
• What is required during a hydrolysis reaction?

  One molecule of water
• What joins the strands of DNA together?

  Nitrogenous bases, with hydrogen bonds between them
• What are the four nitrogenous bases in DNA?

  Thymine, Adenine, Guanine and Cytosine
• What are the two types of nitrogenous base structure?

  Purine and pyrimidine
• What bases have a purine structure?

  Adenine and guanine
• What bases have a pyrimidine structure?

  Thymine, Uracil and Cytosine
• What is the structure of Adenine?

  Purine
• What is the structure of Guanine?

  Purine
• What is the structure of Thymine?

  Pyrimidine
• What is the structure of Uracil?

  Pyrimidine
• What is the structure of Cytosine?

  Pyrimidine
• What bond is between nitrogenous bases?

  Hydrogen bonds
• How many hydrogen bonds are between Adenine and Thymine?

  Two
• How many hydrogen bonds are between Adenine and Uracil?

  Two
• How many hydrogen bonds are between guanine and cytosine?

  Three
• What are the complementary base pairings in DNA?

  Adenine and Thymine, Cytosine and Guanine
• Due to complementary base pairings existing, there will always be equal amount of Adenine and Thymine, and equal amounts of Guanine and Cytosine in each DNA molecule.
• Despite hydrogen bonds alone being quite weak, lots of hydrogen bonds together provide strength to the structure.
• There are more hydrogen bonds between Cytosine and Guanine, so the more of these there are, the more stable the DNA molecule is.
• RNA is a simpler and smaller molecule than DNA.
• What are the nitrogenous bases in RNA?

  Adenine, Uracil, Guanine and Cytosine
• What base is Thymine replaced by in RNA?

  Uracil
• RNA contains the bases Adenine, Cytosine and Guanine, but Thymine is replaced with a different base called Uracil.
• RNA is different from DNA in three ways:

  • The base T is replaced by U
  • The sugar in RNA is ribose, not deoxyribose
  • The nucleotide strand is a single strand, not a double
• DNA and RNA both have a pentose sugar group, however, DNA‘s is deoxyribose, which has a hydrogen group on the second carbon and RNA‘s is ribose, which has a hydroxide group on the second carbon.
• What is the difference between the sugar groups of DNA and RNA?

  DNA has deoxyribose and RNA has ribose