3.2 Nutrition in humans

  • Created by: 14mut64
  • Created on: 11-05-19 20:14

A Balanced Diet

  • Carbohydrates - provide energy; e.g. pasta &r rice
  • Protein  - needed for growth and repair of tissue; e.g. meat & fish
  • Lipids - procide energy, act as an energy store, and provide insulation
  • Vitamins:
    • Vitamin A - helps improve vision and keep skin and hair healthy; e.g. Liver
    • Vitamin C - needed to prevent scurvy; e.g. (citrus) fruit
    • Vitamin D - needed for calcium absorption; e.g. eggs
  • Minerals:
    • Calcium - needed to make bones and teeth; e.g. milk & cheese
    • Iron - needed to make haemoglobin for healthy blood; e.g. red meat
  • Water - needed for every bodily function; e.g. food & drink
  • Dietary fibre - aids the movement of food through the gut; e.g. wholemeal bread & fruit
1 of 3

Digestive Enzymes

  • digestion of carbohydrates:
    • amylase breaks down starch into maltose
    • maltease breaks down maltose into glucose
  • digestion of proteins:
    • protease breaks proteins down into amino acids
  • digestion of lipids:
    • lipase breaks lipids down into glycerol and fatty acids
  • Enzymes are biological catalysts in metabolic reactions.
  • Enzymes can denature if the temperature is too high or the pH is not right.
    • When an enzyme denatures it loses the shape of its active site, meaning that the substrate can no longer fit. 
2 of 3


  • bile is made in the liver and is stored in the gall bladder
  • bile is an alkali that neutralises stomach acids in the small intestine
  • bile also emulsifies lipids and breaks them down into smaller droplets
3 of 3


No comments have yet been made

Similar Biology resources:

See all Biology resources »See all 3.2 Nutrition in humans resources »