A Level Science Applications Support Booklet: ChemistryContentsINTRODUCTION 11 – THE CHEMISTRY OF LIFE :.............................................................................................................31.1 – Introduction.............................................................................................................................3Water – Life’s matrix..........................................................................................................3Importance of hydrogen bonding to life .............................................................................5Condensation polymerisation ............................................................................................5Shaping up ........................................................................................................................61.2 – Protein chemistry....................................................................................................................6a) Proteins - the workhorses of life ........................................................................................6b) Amino acids - the building blocks of proteins ....................................................................8Common features of amino acids...............................................................................8The ionisation of amino acids ...................................................................................10c) Structure - the key to protein function .............................................................................11Condensation polymerisation of amino acids ...........................................................11Levels of protein structure ........................................................................................12The primary structure of proteins..............................................................................12The secondary structure of proteins .........................................................................13Protein tertiary structure ...........................................................................................15Haemoglobin – the molecular ‘breathing machine’...................................................17summary and required knowledge .........................................................................................18d) Enzymes – Nature’s catalysts .........................................................................................19Catalytic efficiency....................................................................................................19Shapely molecules ...................................................................................................20The ‘lock and key’ model ..........................................................................................20Competitive inhibition of enzyme activity..................................................................22Non-competitive inhibition of enzymes.....................................................................23Factors affecting enzyme activity .............................................................................25The effect of temperature .........................................................................................25The effect of pH changes .........................................................................................26Chemical denaturation..............................................................................................27Prosthetic groups and coenzymes – ‘little helpers’...................................................28Ion channels in biological membranes .....................................................................29summary and required knowledge .........................................................................................301.3 – Genetic information ..............................................................................................................31a) DNA – the source of heredit