Glucose (AQA AS Biology): Revision Note

The two forms of glucose

• The most well-known simple sugar monomer is glucose

  • Glucose has the molecular formula C₆H₁₂O₆

• Glucose is the most common monosaccharide and is of central importance to most forms of life

• Glucose exists in two structurally different forms – alpha (α) glucose and beta (β) glucose; these structural forms are known as isomers of glucose

  • In alpha glucose:

    • the hydroxyl (OH) group on carbon 1 is located below the ring

  • In beta glucose:

    • the hydroxyl (OH) group on carbon 1 is located above the ring

• Different polysaccharides are formed from the two isomers of glucose