B2

• What tests for starch?

  Iodine
• What is the colour change if starch is present?

  Orange / brown to Black / blue
• What tests for sugar?

  Benedicts
• What is the colour change if sugar is present?

  Blue to Brick red
• What tests for lipids?

  Ethanol
• What is the colour change if ethanol is present?

  Colourless to cloudy
• What tests for protein?

  Biuret
• What is the colour change is protein is present?

  Blue to purple
• What does amylase convert?

  starch to simple sugars
• Where is amylase made?

  • salivary glands
  • pancreas
  • small intestines
• What does proteases convert?

  Proteins to amino acids
• Where are proteases made?

  • pancreas
  • stomach
  • small intestine
• What do lipases convert?

  lipids into glycerol and fatty acids
• Where are lipases made?

  • pancreas
  • small intestine
• Where is bile produced?

  Liver
• Where is bile stored?

  Gallbladder
• Where is bile released?

  Small intestine
• what does bile do?

  • neutralises stomach acid
  • emulsifies fats
• Why are enzymes used in digestion?

  To mix with food and break down big molecules
• In digestion, where are enzymes released?

  The gut
• state 3 examples of big molecules

  • starch
  • protein
  • fats
• What smaller molecules do digestive enzymes break big molecules down into?

  • amino acids
  • fatty acids
  • sugars
  • gylcerol
• Why are big molecules broken into smaller molecules?

  They are soluble so they can easily pass through the digestive systems walls allowed them to be absorbed into the blood stream
• What happens in an enzyme reaction when there is an increase in temperature?

  Rate of reaction increases due to increased collisions with enzyme and substrate
• What happens in the reaction if enzymes reach optimum temperature?

  Enzymes denature
• What happens if an enzyme denatures?

  The active site changes shape meaning it no longer fits substrate
• Place the cell organisation structure into the order of smallest to largest

  • cell
  • tissue
  • organ
  • organ system
  • organism
• What are enzymes?

  Biological catalysts made up of proteins
• What are catalysts?

  Substances that increase rate of chemical reactions without being used up
• What is the lock and key theory?

  A model explaining the enzyme actions - the active site has a unique shape that is specific to each substrate
• What is a substrate?

  a substance the enzyme acts on
• What part of the body are the lungs in?

  The Thorax
• What separate the thorax and lower part of the body?

  Diaphragm
• What are lungs?

  Big pink like sponges protected by the rib cage and surrounded by pleural membranes
• Where does the air that you breathe go?

  The trachea which splits into two tubes called the bronchi - one goes into each lung
• What do the bronchi split into?

  The bronchioles
• where do the bronchioles end?

  At small bags - the alveoli
• What does the alveoli carry out?

  Gas exchange
• What are the alveoli?

  Little air sacs surrounded by a network of blood capillaries
• What does the blood passing next to the alveoli contain?

  Lots of carbon dioxide and

  very little oxygen