1.9 Water

• Properties

  • metabolite
  • solvent
  • high heat capacity
  • large latent heat of vaporisation
  • strong cohesion
• Metabolite

  component of metabolic reactions including condensation and hydrolysis
• Solvent

  Able to dissolve a wide range of substances
• High heat capacity


  Water's ability to absorb and retain heat
• Large latent heat of vaporisation


  Provides a cooling effect with little loss of water through evaporation
• Strong cohesion


  produces surface tension highest cohesion of any non metal
• Roles of water

  • solvent
  • transport medium
  • coolant
  • habitat
• Solvent properties


  • good at dissolving ions and polar molecules
  • able to dissolve a wide range of substances
• Solvent examples


  • glucose dissolves in water and is stored in the vacuole
  • trees and plants take up minerals
  • bacteria cytosol is mainly water
• Transport medium properties


  • substances dissolve
  • high cohesion
• transport medium examples


  xylem
• Coolant properties


  • high temp stability
  • affected by temp
• coolant examples


  frogs stay cool in summer and warm in winter
• Habitat properties


  • ice is less dense, it floats
  • ice is insulating
• Habitat examples

  • polar bears and seals have habitats
  • blue whales can still swim