Enzymes

• What are enzymes?


  Biological catalysts
• Why is the word biological used?


  Because they function in living systems.
• Why is the word catalyst used?


  Because they speed up the rate of chemical reaction without being used up or changed.
• What do enzymes do in biological reactions?


  Lower the activation energy.
• Enzymes can be intracellular or extracellular, what does this mean?


  It refers to whether they're active inside or outside the cell.
• What are intracellular enzymes?


  They're produced and function inside the cell.
• What are extracellular enzymes?


  They're secreted by cells and catalyse reactions outside cells (e.g. digestive enzymes).
• What is the active site?- how many amino acids does it consist of, where is it found?


  It is an indented area, consisting of between 6-10 amino acids, which is found on the surface of an enzyme molecule.
• What is fundamental to an enzymes ability to act as a biological catalyst?


  The unique shape of the active site.
• What is the allosteric site?


  It is away from the active site, that is able to bind to enzymes.
• What is made when an enzyme binds to the substrate?


  An enzyme-substrate complex
• What do enzymes do to the substrate?


  They bend the bonds in substrate molecules into unstable position and this allows them to be much more easily broken.