sugars

• sugar


  sugar is the general term for mono and disaccardies and are the basic bulding blocks of carbohydrates
• Monosaccharides

  Monosaccharides are the simplest form of carbohydrates, also known as 'simple sugars'. Monosaccharides are soluble, sweet-tasting and are found in many foods such as fruits, vegetables, and grains.

  They have the general formula (CH2O)n where 'n' can be any number from 3 to 7.

  Monosaccharides are classified according to the number of carbon atoms in each molecule:

  Pentose sugars (5 carbon atoms)

  • Ribose
  • Deoxyribose

  Hexose sugars (6 carbon atoms)

  • Glucose
  • Fructose
• Alpha-glucose and beta-glucose 

  Glucose is a hexose (6-carbon) sugar with the formula C6H12O6. The atoms in glucose can be arranged in two different ways.

  This means that there are two isomers of glucose: 

  1. Alpha-glucose (α-glucose)
  2. Beta-glucose (β-glucose)

  
• this shows all the atoms

  
• Properties and uses of glucose

  Glucose is used as the primary energy source in animals and plants.

  The following features of glucose help it to function as an energy source: 

  • It is soluble The hydroxyl groups can form hydrogen bonds with water, so it can be transported around organisms.
  • Its bonds store lots of energy - This energy is released when the bonds are broken.
• Disaccharides

  Disaccharides are formed when two monosaccharides join together. Examples of disaccharides include maltose (found in grains and cereals), sucrose (used as a transport sugar in plants), and lactose (the main carbohydrate found in milk).

  • Maltose is made up of glucose joined to glucose.
  • Sucrose is made up of glucose joined to fructose.
  • Lactose is made up of glucose joined to galactose.
• Disaccharide formation and breakdown

  Disaccharides are created via condensation reactions, and broken down via hydrolysis reactions. These reactions involve the formation or the breakdown of a covalent bond known as a glycosidic bond.

  Condensation reaction

  
• hydrolysis reaction When a water molecule (H2O) is added to a disaccharide, the glycosidic bond is broken to release the 2 monosaccharides