Biology-Enzymes

• Enzyme is important proteins that control chemical reactions in all living organisms
• Each enzyme is specific to an individual reaction and requires certain conditions to function efficiently
• Sum of all these reactions in an organism/cell is called metabolism
• Enzymes are made up of long chains of amino acids that are folded into specific shapes
• 'Lock and key' model - all enzymes have an active site which is where it will bind to a substrate
• enzymes and active sites have specific shapes, means only certain substrates can bind to it and form enzyme-substrate complexes.
• each enzyme can only catalyse one specific type of reaction and therefore produce the products
• Induced fit model suggests that when the substrate enters the active site, the shape changes slightly so that it fits better with the substrate

  
• the rates of enzymes are controlled reactions are affected by the temperature and PH
• When the shape of the active site changes, substrates cant bind, enzyme-substrate complexes won't be able to form and enzymes will stop catalysing the reaction
• The rate of an enzyme can also be increased by increasing the concentration of the substrate

  
• Trypsin has an optimum ph of 7-9 which breaks down proteins into peptides and works well in alkaline conditions of the small intestines