biology - digestion

• Defintion of food

  nutritious substance plants/ animals drink/eat to grow
• nutrition

  the process of providing or obtaining the food necessary for health and growth.
• balanced diet

  where wide variety of foods are eaten in the right proportions
• what are the food groups

  sugars, polysaccharides, water, protein, lipids, fibre, mineral ions, vitamins
• can the amount of energy needed by two people differ

  yes
• how to work out energy in the energy content of foods experiment

  energy = masschange in temp42
• what are proteins for

  muscle growth and repair
• what are fats for

  cell functions, body heat, fast release energy
• what enzyme is present in the mouth

  amylase
• what is the muscular process in the oesophagus

  peristalsis
• is stomach acid an enzyme

  no
• what is bile

  an emulsifier
• how is pancreas involved in digestion

  not directly, makes all enzymes
• why can't you absorb complex carbs, proteins or fats into blood

  too large to pass through lining of blood vessels
• what are enzymes

  catalysts
• what do enzymes do

  help speed up the process of chemical reactions without being changed
• what are carbohydrases

  enzymes that break down carbohydrates
• what do carbohydrases break down carbs into

  simple sugars
• where are carbohyrdrases made

  mouth, pancreas, small intestine
• what do proteases break down

  proteins
• what are proteins broken down into

  amino acids
• where are proteases made

  Stomach, pancreas, small intestine
• what do lipases break down

  fats
• what are fats broken down into

  fatty acids and glycerol
• where are lipases made

  Pancreas and small intestine
• what are enzymes made of

  proteins
• how are enzymes specific

  Each enzyme can only bind to one type of substrate
• what does amylase break down

  starch
• true or false: fibre is indigestible because we do not produce the enzyme cellulase

  true
• what is the theory on how an enzyme breaks down a substrate called

  the locke and key model
• what do the enzyme and substrate do for the reaction to occur

  collide and bind
• what can reactions do

  make big molecules into small, small to big, one to another
• what factors affect how enzymes function

  concentration, pH, temp
• what happens to an enzyme that is irreversible

  denaturing