Enzymes

• what are enzymes?

  a type of catalyst that’s made by living organisms sometimes called biological catalyst
• Catalyst

  A substance that increases the speed of reaction without being changed or used up in the process
• If the substrate doesn’t fit the active site then the reaction won’t be…?

  Catalysed
• What is the active site?

  a part of the enzymes with a unique shape that’s complementary to the substrate of the reaction
• What is the lock and key model?

  Scientist thought that the substrate had to fit perfectly to the active site. meaning enzymes can only catalyse specific reactions. 
• What is the induced fit model?

  The enzyme changes shape slightly as it binds to the substrate(the active site is complementary to the substrat)
• Optimum temperature 


  The temperature in which it works best, allowing it to catalyse reactions at its highest rate. This temp varies depending on the enzyme
• Optimal PH


  The optimal pH for an enzyme is the pH level where it works best, speeding up reactions at its highest rate in the body or its specific environment.
• What happens if the temperature is higher than the optimum temperature?

  The high temperature starts to break some of the bonds holding the enzyme together and the active site starts to change shape to the point where the enzyme becomes denatured and the substrate won’t be able to fit in the active site.
• if the ph is too high or too low it will lower the rate of reaction


  This is because some of the bond holding the enzyme together start to break, so the active site starts to change shape.
• Types of carbohydrates and what enzyme is it broken down by?

  1. Pasta, potatoes. Rice
  2. amylase
• What different places is amylase made

  Salivary glands, pancreas and small intestines
• What is the main thing amylase breaks down?

  Starch
• Types of protein and what enzymes is it broken down by?

  1.Nuts, meats and beans

  2.Protease into amino acids
• What 3 places is protease made in?

  Stomach(pepsin), pancreas, and small instestine
• Types of fat(lipids) and what enzyme is it broken down by?

  Types of fat:cheese, oil, chocolate

  broken down by: lipases into fatty acids and glycerol
• What different places are lipases made from?

  Pancreas and small instestine
• Are most chemical reactions naturally fast or slow?


  Slow
• Enzymes


  • They are large proteins made up of long chains of amino acids
  • They can fold into different shapes, each shape catalyzing a particular chemical reaction
• How enzymes work


  1. Enzyme has an active site with a unique shape

  2. Substrate fits into active site

  3. Enzyme speeds up the chemical reaction
• Substrate


  Reactant in a chemical reaction
• Products


  Smaller pieces that a substrate is broken into
• Enzymes speed up chemical reactions without being changed or used up in the process
• Lock and key model


  • Substrate has to fit perfectly into the active site of the enzyme
• Induced fit model


  • Enzyme changes shape slightly to better fit the substrate
• The induced fit model is more realistic than the lock and key model
• Enzymes allow living cells to carry out a huge number of chemical reactions every second
• Increasing temperature


  Can increase the rate of chemical reactions
• High temperatures can damage cells and speed up unwanted reactions
• Catalyst


  A substance that increases the speed of a chemical reaction without being changed or used up in the process
• • Heating our cells more would require a lot of energy
  • Higher temperatures could damage our cells
  • Higher temperatures would also speed up non-useful reactions