Respiration and Metabolism

• Respiration


  The process of transferring energy from the breakdown of glucose (sugar)
• Respiration is not breathing in and breathing out
• Respiration goes on in every cell in your body continuously
• Respiration happens in plants too, all living things respire
• Respiration is the process of transferring energy from glucose
• Respiration is exothermic, it transfers energy to the environment
• Respiration


  • Transfers energy for building up larger molecules from smaller ones
  • Allows muscles to contract so organisms can move about
  • Keeps body temperature steady in colder surroundings (in mammals and birds)
• Metabolism


  All the chemical reactions in an organism
• In a cell there are lots of chemical reactions happening all the time, which are controlled by enzymes
• Metabolic reactions


  1. Reactant

  2. Enzyme

  3. Product

  4. Enzyme

  5. Product
• Reactions forming larger molecules

  • Glucose molecules joined to form starch, glycogen, cellulose
  • Glucose and nitrate ions combined to make amino acids, then proteins
  • One glycerol and three fatty acids combined to make lipid molecules
• Reactions breaking down larger molecules

  • Glucose broken down in respiration
  • Excess protein broken down to produce urea, which is excreted
• The sum of all the reactions happening in a cell or the body is called its metabolic rate