2. Polysaccharides

• What are polysaccharides

  Are composed of hundreds of thousands of monosaccharides combined together. these monosaccharides are joined together through many condensation reactions. 
• Exampl s of polysaccharides  

  • Starch
  • Cellulose
  • Glycogen

  Functions include structural support and storage, they are insoluble (no

  Functions include structural support and storage, they are insoluble (no osmotic effect)
• Starch is made up of

  2 polysaccharides of a alpha glucose:

  • Amylose
  • Amylopectin
• Amylose

  • Alpha Glucose monomers
  • 1,4 glycosidic bonds
  • Straight chain
  • Coiled
• Amylopectin

  • Alpha Glucose monomers
  • 1,4 + 1,6 glycosidic bond
  • Branched

  Rapidly hydrolyse to release energy
• Glycogen

  • in animals
  • is a highly branched polymer of alpha-glucose
  • Its branched structure, similar to amylopectin (a starch component),
  • allows for rapid release of glucose when energy is needed
  • Is compact
  • Is insoluble
  • cannot easily diffuse out of cell
• Glycogen is more branched than amylopectin, so It is more compact.
• Cellulose

  • Cellulose is a polymer consisting of long chains of β-glucose joined together by 1,4 glycosidic bonds
  • As β-glucose is an isomer of α-glucose, consecutive β-glucose molecules must be rotated 180° to each other in order to form the 1,4 glycosidic bonds
  • Due to the inversion of the β-glucose molecules many hydrogen bonds form between the long chains, giving cellulose it’s great strength