Properties of Water

3 Biological Importances of Water

medium for metabolic reactions in cells

polar molecule

hydrogen bonds form due to polarity

Hydrogen bonds

Weak H+ bonds caused by the attraction between negative Oxygen atoms and positive Hydrogen atoms in diff H2O compounds

Properties bc of Hydrogen bonds

Solvent

Metabolite

Cohesion

High Specific Heat Capacity

Latent Heat of Vaporisation

Solvent

H2O is a universal solvent

due to polarity, many ions & covalently bonded polar molecules will dissolve in it

allows chemical reactions to occur in cells bc dissolved solutes are more reactive when free

allows metabolites to be transported efficiently (except non-polar which are hydrophobic)

Metabolite

Metabolite = involved in chemical reactions eg condensation and hydrolysis reactions

Condensation reaction - smaller molecules combine forming a larger molecule with the removal of H2O

Hydrolysis reaction - H2O is added to break a bond in a large molecule, splitting into smaller units

Cohesion

Cohesion = attraction between molecules of the same type

H+ bonds between water molecules allow strong cohesion between water molecules

Allows: *water to move thru the xylem of plants & blood vessels of animals

*surface tension where water meets air, H+ bonds occur between the top layer creating a film on top of the water

H2O can also create H+ bonds with other molecules (known as adhesion) also allows water to move up xylem

High Specific Heat Capacity

Latent Heat of Vaporisation