Organisation

• Explain, using an example, why the digestive system is considered an 'organ system'?

  • The digestive system is considered an organ system because it consists of a group of organs...
  • that work together to perform the common function
  • of digesting and absorbing our food 
  • For example the pancreas releases digestive enzymes which help break down the food molecules, while the small intestine absorbs the nutrients
• Explain how high/low pH can cause an enzyme to denature?

  1. High/ Low pH can cause the bonds between the enzymes to break
  2. This causes the active site to change shape
  3. This means the enzyme will no longer be complementary to the substrate
  4. This means the it can longer form an enzyme-substrate complex.
• Why don't we increase the temperature of the body to increase the rate of reaction?


  1. Require lots of energy
  2. Damage cells
  3. Speed up non-useful reactions
• What does disease mean?


  The term 'disease' refers to a group of conditions that can cause ill health.
• test for protein

  Biuret Reagent

  Blue to lilac / purple
• Test for sugars

  Benedict's Solution and heat

  blue to brick red
• test for starch

  iodine solution

  Orange to blue / black
• test for fats


  Ethanol + water

  Clear to cloudy white layer