Enzymes

• Amylase


  Apart of carbohydrates/carbohydrase

  -breaks starch down into glucose
• Protease


  -a protein

  -breaks down proteins into amino acids
• Lipase


  -a fat

  -breaks down lipids into fatty acids and glycerol
• Enzyme


  A biological catalyst- they are proteins
• Mouth

  In saliva there is amylase
• Pancreas


  Trypsin(protease)

  lipase

  amylase
• Stomach

  Pepsin(protease)

  hydrochloric acid
• Small intestine


  -trypsin(protease)

  -microvilli absorbs nutrients
• Gallbladder


  emulsifies fats to increase emulsifies fats to increase surface area
• polymers


  long chain of molecules
• monomers


  short chain of molecules
• substrate


  the substance the enzyme works on

  e.g amylase works on the polymer starch to break it down into the monomer of glucose
• denatures


  the active site of an enzyme has changed and no longer works, it no longer fits the shape of the substrate
• Lock and Key Mechanism


  1.The substrate has a specific shape and goes into the active site with a complementary shape

  2.this creates a enzyme -substrate complex, the enzyme speeds up the reaction by bringing them close together,it holds the substrates tightly while they react

  3.the active site then releases the product which is now a slightly different shape from before
• Test for starch


  Iodine solution- changes to black/blue when starch is present
• Glucose(reducing sugars)


  Benedicts Solution -changes from a blue to a orange/red/ green depending on the amount of glucose present
• monosaccharides

  simple sugar such a glucose, only one
• disaccharide’s

  2 monosaccharides
• polysaccharides


  long chain of monosaccharides
• carboydrase


  a carbohydrate - break down disaccharides and polysaccharides into monosaccharides
• carbohydrates include


  glycogen, glucose, starch and enzymes
• calorimeter 


  a machine used to measure the amount of energy in food
• calorimetry


  the process which samples are burned and we can measure the amount of energy from the combustion
• What denatures/changes enzymes?


  -temperature-temperature

  -not being at optimal conditions

  -pH level
• low temperature


  • there is less energy in the particles meaning less collision happen so the reaction is slowed down
• optimal conditions 


  enzymes work best at these conditons
• optimal temperature


  enzymes for example in the body work best at the bodys temperature of 37degrees celsius
• high temperature


  it denatures and changes the shape of the active site
• low pH


  -as the pH increases, the rate of the enzymes activity increases, at low its just slowed down
• High pH


  -this denatures and changes the shape of the active site
• optimal pH


  the best pH enzymes work out eg pH 7 for amylase in your saliva
• Substrate concentration -low


  as concentration increases so does the rate of reaction, its slower down when its low as there will be more substrate that enzymes can digest
• substrate concentration high


  there isnt enough enzymes for it to digest the substrate it will remain at the same activity
• test for reducing sugars


  benedicts solution can go red,orange or green depending on the amount of sugar
• test for protein


  biuret test goes purple if protein is present
• test for lipids


  alcohol emulsion goes cloudy if fats are present
• emulsify


  to make into small droplets
• gallbladder


  emulsifies fats