1.7 water ❤️

How do hydrogen bonds occur between water molecules

• water is a polar molecules

• So slightly negatively charged oxygen atoms attract slightly positively charged hydrogen atoms of other water molecules

Name 5 properties of water that are important in biology

• metabolite

• Solvent (can dissolve solutes)

• Relatively high specific heat capacity

• Relatively large latent heat of evaporation

• Strong cohesion between water molecules

Properties of water and their importance: metabolite

Used in condensation/ hydrolysis/ respiration/ photosynthesis

Properties of water and their importance: solvent

• allows metabolic reactions to occur (faster in solution)

• Allows transport of substances

Properties of water and their importance: relatively high specific heat capacity

• buffers changes in temperature, as it can gain/lose a lot of heat/energy without changing temperature

• Good habitats for aquatic organisms as temp is more stable

• Helps organisms maintain a constant internal body temperature

Properties of water and their importance: relatively large latent heat of vaporisation

• allows effective cooling via evaporation of a small volume (e.g sweat)

• So helps organisms maintain a constant internal body temperature

Properties of water and their importance: strong cohesion between water molecules

• supports columns of water in tube-like transport cells of plants

• Produces surface tension where water meets air, allowing small organisms to walk on water