• Monosaccharides?can join together via?condensation reactions?to form?disaccharides
  • A condensation reaction is one in which two molecules join together via the formation of a new chemical bond, with a?molecule of water?being?released?in the process
  • The new chemical bond that forms between two monosaccharides is known as a?glycosidic bond
  • To calculate the chemical formula of a disaccharide, you add all the carbons, hydrogens and oxygens in both monomers then subtract 2x H and 1x O (for the water molecule lost)

   

• Common examples of disaccharides include:
  • Maltose?(the sugar formed in the production and breakdown of starch)
  • Sucrose?(the main sugar produced in plants)
  • Lactose?(a sugar found only in milk)

   

• All three of the common examples above have the formula?C12H22O11

Common Disaccharides and their Monosaccharide Monomers Table

The disaccharide maltose is formed from two α-glucose monomers (sub-units)

The disaccharide sucrose is formed from α-glucose and fructose monomers (sub-units)