resperation

• Respiration


  A chemical reaction carried out in all living organisms
• Respiration


  1. Energy is released from glucose

  2. Either in the presence of oxygen (aerobic respiration)

  3. Or the absence of oxygen (anaerobic respiration)
• The reactions ultimately result in the production of carbon dioxide and water as waste products
• Energy


  Transferred in the form of ATP
• Organisms need energy for

  • Chemical reactions to build larger molecules from smaller molecules
  • Muscle contraction to allow movement
  • Keeping warm (to maintain a constant temperature suitable for enzyme activity)
• Cellular respiration


  An exothermic reaction that is continuously occurring in living cells
• Cellular respiration

  The chemical process that releases energy from glucose
• ATP


  The molecule that energy is transferred via
• ATP


  Produced in respiration in the mitochondria
• ATP


  Required for living processes to occur within cells and organisms
• Aerobic respiration


  Requires oxygen, complete breakdown of glucose, produces carbon dioxide and water, releases a lot of energy
• Anaerobic respiration


  Does not require oxygen, incomplete breakdown of glucose, in animal cells produces lactic acid, in yeast produces carbon dioxide and ethanol, releases a little energy
• Comparing Aerobic & Anaerobic Respiration


  1. Oxygen needed

  2. Glucose breakdown

  3. Products

  4. Energy released
• Aerobic respiration


  The chemical reaction in cells that uses oxygen to break down nutrient molecules to release energy
• Aerobic respiration


  • Requires oxygen
  • Is the complete breakdown of glucose to release a relatively large amount of energy for use in cell processes and reactions
  • Produces carbon dioxide and water as waste products as well as releasing useful cellular energy
• Aerobic Respiration Word Equation

  Glucose + Oxygen → Carbon Dioxide + Water
• One molecule of glucose combines with six molecules of oxygen to produce six molecules of carbon dioxide and six molecules of water
• Anaerobic respiration


  Does not require oxygen
• Anaerobic respiration


  The chemical reaction in cells that breaks down nutrient molecules to release energy without using oxygen
• Anaerobic respiration involves the incomplete breakdown of glucose and so releases a relatively small amount of energy for use in cell processes
• Different breakdown products are formed depending on the type of organism that the anaerobic respiration is taking place in
• You need to know the equations for anaerobic respiration in


  • Animals
  • Plants (or fungi)
• Anaerobic respiration in animals

  • Mainly takes place in muscle cells during vigorous exercise
  • When we exercise at high intensities, our muscles have a higher demand for energy
  • Our bodies can only deliver so much oxygen to our muscle cells for aerobic respiration
  • When oxygen runs out, glucose is broken down without it, producing lactic acid instead
  • Glucose has not been fully broken down meaning there is still energy stored within the bonds of lactic acid molecules
• Anaerobic respiration releases less energy than aerobic respiration
• Lactic acid


  Builds up in muscle cells and lowers the pH of the muscle tissue (making the conditions more acidic)
• Acidic conditions


  Can denature the enzymes in cells
• Breaking down lactic acid


  Using oxygen to produce carbon dioxide and water as waste products
• Oxygen debt


  The amount of oxygen required to break down the lactic acid that has built up
• Repaying the oxygen debt


  The process of breaking down the lactic acid
• Anaerobic respiration in plants and fungi


  • Plants and yeast can respire without oxygen, breaking down glucose in the absence of oxygen to produce ethanol and carbon dioxide
• Economically important fermentation


  • Manufacture of bread (where the carbon dioxide produced helps the dough to rise)
  • Brewing (where the ethanol produced makes beer)
• Contents of Tube A

  • TUBE A
• Contents of Tube B


  • TUBE B
  • COLOUR CHANGE
  • GERMINATING SOAKED SEEDS
• Contents of Tube B


  • NO COLOUR CHANGE
  • DEAD BOILED SEEDS
• Contents of Tube B


  • LAYER OF COTTON WOOL
  • LAYER OF COTTON WOOL
• Contents of Tube B


  • HYDROGENCARBONATE INDICATOR SOLUTION
  • HYDROGENCARBONATE INDICATOR SOLUTION