3.1.2 Carbohydrates

• Glycosidic bond

  A condensation reaction between two monosaccharides
• Maltose = Glucose + Glucose
• Sucrose = Glucose + Fructose
• Lactose = Glucose + Galactose
• Benedict’s Solution

  1. Liquid Sample
  2. Neutral solution
  3. Add Benedict’s Reagent
  4. Heat in boiling water

  • Blue to Brick Red
• Non-Reducing Sugar

  1. Add Acid
  2. Neutralise. (Add excess of Base)
  3. Normal process of Benedict’s Reagent
• Disaccharides

  Formed by the condensation of two monosaccharides.
• Starch is made of Amylose and Amylopectin
• Amylose

  Forms 1,4 - glycosidic bonds
• Amylopectin

  1,4 & 1,6 - glycosidic bonds
• Glycogen function

  Main storage polymer of a-glucose in animal cells.
• Glycogen structure


  1,4 & 1,6 glycosidic bondS
• Cellulose function

  Polymer of b-glucose, gives rigidity to plant cell walls
• Cellulose structure

  1,4 glycosidic bonds
• Function of monosaccharides

  • Source of energy in respiration
  • Building blocks for polymers