organisation

• what is the definition of a organ 


  . a group of different tissues working together to perform a common function
• why is the digestive system considered a organ system

  because it contains a group of organs that work together to perform the common function of digesting and absorbing our food
• what are enzymes ?

  type of catalyst that is made by living organisms called biological catalysts
• how do enzymes work ?

  they speed up chemical reactions lowering energy needed
• what is the lock and key model ?


  Model of enzyme-substrate interaction.
• 2 reasons why we can’t make o ur cells even warmer to increase the rate of reactions ?

  heating out cells would require a lot of energy . higher temperatures could damage our cells
• factors that effect the rate of reaction and functioning of enzymes

  temperature, ph
• what do we call a enzyme that doesn’t bind to the substrate

  de natured
• what does the term optimum mean for enzyme temperature

  the temperature at which enzyme activity is highest
• explain how increasing the temperature can cause an enzyme to denature ?

  high temperatures start to break the bonds holding the enzyme together this causes the enzymes and its active site to change shape this means the enzymes active site will no longer be complementary to the substrate
• what are nutrients ?

  Substances essential for growth, development, and maintenance of the body.
• how do lipids and fats help humans ?

  Energy, insulation, cell structure, hormone production.
• what are vitamins ?

  Essential nutrients organic molecules
• what are minerals ?


  Inorganic substances with a specific chemical composition and crystal structure.
• what is the role of fibre ?

  Digestion stops us getting constipation
• what is the role of water in our body ?

  Hydration. replace what we have lost from sweating
• why do we need carbohydrates ?

  Energy
• what food group do fats and oils make up

  lipids
• why do we need lipids ?


  Energy storage, cell membrane structure, insulation, and hormone production.
• which disease can be cause by a lack of vitamin c ?


  Scurvy
• why is iron important in our diet 


  component of haemoglobin. which is the protein in red blood cells that allows them to transport oxygen around the body a lack of iron can lead to anaemia
• what are biological molecules ?

  Molecules found in living organisms and produced by cells
• what are nutrients ?


  Substances essential for growth, development, and maintenance of the body.
• what are monomers that join together to form proteins called ?

  amino acids
• what enzyme is carbohydrate broken down by ?

  Amylase
• which enzyme breaks down proteins ?

  Protease
• which enzyme breaks down lipids ?

  Lipase
• what is carbohydrates broken down into by enzymes ?

  maltose
• what is proteins broken down into

  amino acids
• what are lipids broken down into

  glycerol and fatty acids
• what is starch broken down into ?


  Glucose
• how does bile help with the digestion of lipids ?

  Emulsifies the lipids which increases the surface area
• how does the digestive system digest food ?

  Enzymes.
• how the digestive system absorbs food ?

  Absorption
• how do we break down food 


  breakdown food by physically chewing then the saliva from the salivary glands makes the food softer and easier to be broken down
• what is the role of the gullet ?


  Swallowing
• what is the role of the stomach ?


  contracts muscular walls, uses pepsin breaks down proteins and produces hydrochloride acid which kills bacteria
• what are the main roles of gall bladder ?


  releases bile which neutralises acid from the stomach. emulsifying fats which gives fats much bigger surface area. BILE IS STORED IN GALL BLADDER MADE IN LIVER
• what is the pancreases role

  it has lots of digestive enzymes, produces enzymes to aid digestion pancreatic juices
• how is villi adapted to its role ?

  there are many villi which gives them a large total surface area over which to absorb nutrients they have a single layer of cells on their surface which means nutrients only have to diffuse a short distance. good food supply