Respiration

• Cellular respiration


  Exothermic reaction

  
  

  Continuous in living cells

  
• Aerobic


  Using oxygen

  
  

  Transfers lots of energy

  
• Mitochondria


  Site of aerobic respiration

  
  

  Contain enzymes

  
  

  Rod shaped organelles

  
  

  Found in plant, animal, fungi and algae cells

  
• Active cells


  Contain more mitochondria

  
• Anaerobically


  Without oxygen

  
  

  Transfers a little energy

  
• Cytoplasm


  Site of anaerobic respiration

  
• Energy used for:

  
  

  Chemical reactions to build larger molecules


  Synthesis reactions

  
• Energy used for:

  
  

  Movement


  Muscle cells contract

  
• Energy used for:

  
  

  Keeping warm


  Mammals and birds maintain a constant body temperature

  
• Energy is used for:

  
  

  Moving mineral ions in plants

  e.g nitrate ions required to make amino acids

  
  

  Moved from soil into root hair cells

  
• Active transport

  Movement from low to high concentration

  
  

  Against concentration gradient

  
  

  Requires energy from respiration

  
  

  Can happen in plant and animal cells

  
• Carbon dioxide

  
• Anaerobic respiration in muscles

  
• Incomplete oxidation of glucose

  In anaerobic respiration

  
  

  Less energy is transferred compared to aerobic respiration

  
• Anaerobic respiration in plant and yeast cells


  Learn the word equation

  
• Fermentation


  Anaerobic respiration in yeast cells

  
  

  Economic importance

  
  

  Manufacture of bread and alcoholic drinks

  
• Increase during exercise


  Heart rate

  Breathing rate

  Breath volume

  
  

  = supply more oxygenated blood

  
• Insufficient oxygen supply during exercise

  Anaerobic respiration produces lactic acid in muscles

  
• Oxygen debt


  The extra oxygen that must be taken into the body after exercise

  
  

  To breakdown the lactic acid

  
• Muscle fatigue


  During long periods of vigorous activity

  
  

  Muscles stop contracting efficiently

  
• Lactic acid


  Produced by anaerobic respiration in muscles

  
  

  Either broken down into carbon dioxide and water (no more energy is released, needs oxygen)

  
  

  Transported in blood to liver to be made into glucose again

  
• Glycogen


  Carbohydrate store in animals

  
  

  Especially liver and muscle cells

  
  

  Insoluble

  
  

  Can be converted back into glucose