Formation and properties of disaccharides

• What is a disaccharide?

  A carbohydrate made of two monosaccharides
• How do the components of lactose differ from those of sucrose?

  Lactose contains galactose, sucrose does not
• What is the source of lactose?

  Milk
• What are the three main disaccharides found in food?

  • Sucrose
  • Lactose
  • Maltose
• What is the bond that joins monosaccharides in disaccharides?

  Glycosidic bond
• How do the common disaccharides differ?

  In their monosaccharide arrangements
• What is the chemical structure of lactose?

  Galactose-glucose
• What does lactose link together?

  A 6-membered galactose and glucose
• What happens during a dehydration synthesis reaction in disaccharides?

  A water molecule is removed
• What type of reaction forms a glycosidic bond in disaccharides?

  Dehydration synthesis reaction
• What is the IUPAC name for the compound 2,3-dihydroxynaphthalene?

  Naphthalene-2,3-diol
• What is the chemical formula for 2,3-dihydroxynaphthalene?

  $C_{10}H_{8}O_{2}$
• How do the structures of sucrose, lactose, and maltose differ?

  • Sucrose has a glucose and fructose unit
  • Lactose has a galactose and glucose unit
  • Maltose has two glucose units
• What type of glycosidic bond is formed when glucose and fructose join to make sucrose?

  (1→2) glycosidic bond
• Which two monosaccharides combine to form sucrose?

  Glucose and fructose
• What process forms disaccharides from monosaccharides?

  Dehydration synthesis
• What is the chemical structure of sucrose?

  Glucose-fructose
• What type of bond forms between monosaccharides during dehydration synthesis?

  Glycosidic bond
• What is the chemical structure of maltose?

  Glucose-glucose
• What is the significance of water being released during the formation of sucrose?

  It indicates a dehydration synthesis reaction occurred
• How are monosaccharides in a disaccharide linked together?

  By a glycosidic bond
• What are the components of sucrose, lactose, and maltose?

  • Sucrose: Glucose + Fructose
  • Lactose: Galactose + Glucose
  • Maltose: Glucose + Glucose
• What are disaccharides?

  Carbohydrates formed from two monosaccharides
• What are disaccharides primarily involved in within biological systems?

  Energy storage and transport
• How are disaccharides formed?

  By two monosaccharides joining through dehydration synthesis
• How does the structure of 2,3-dihydroxynaphthalene compare to that of naphthalene?

  • Naphthalene has a fused benzene ring structure without any substituents
  • 2,3-dihydroxynaphthalene has the same naphthalene ring system but with two hydroxyl (-OH) groups attached at the 2 and 3 positions
  • The addition of the hydroxyl groups changes the chemical and physical properties compared to the parent naphthalene compound
• What is the chemical structure of sucrose?

  Glucose-fructose
• What are the key structural features of sucrose, lactose, and maltose?

  • Sucrose: Glucose-fructose disaccharide
  • Lactose: Galactose-glucose disaccharide
  • Maltose: Glucose-glucose disaccharide
• How do the structures of sucrose, lactose, and maltose differ?

  • Sucrose has a glucose and fructose unit
  • Lactose has a galactose and glucose unit
  • Maltose has two glucose units
• What is the chemical structure of maltose?

  Glucose-glucose
• What is the difference between maltose and sucrose in terms of their components?

  Maltose has two glucose units, sucrose has fructose
• What does maltose consist of?

  Two identical 6-membered glucose rings
• What is the source of maltose?

  Malt drinks
• What are the key structural features of 2,3-dihydroxynaphthalene?

  • Contains a naphthalene ring system
  • Has two hydroxyl (-OH) groups attached at the 2 and 3 positions
  • The molecular formula is $C_{10}H_{8}O_{2}$
• What is the chemical structure of lactose?

  Galactose-glucose
• What is the source of sucrose?

  Table sugar
• What are the key structural features of sucrose, lactose, and maltose?

  • Sucrose: Glucose-fructose disaccharide
  • Lactose: Galactose-glucose disaccharide
  • Maltose: Glucose-glucose disaccharide
• Which disaccharide transports glucose during digestion?

  Maltose
• How do the structures of sucrose, lactose, and maltose differ?

  • Sucrose has a glucose and fructose unit
  • Lactose has a galactose and glucose unit
  • Maltose has two glucose units
• What do the three common disaccharides share in structure?

  Similar ring structures and glycosidic bonds