Respiration

• Types of respiration

  • Aerobic respiration
  • Anaerobic respiration
• Breathing in (exhalation)

  Diaphragm relaxes and moves upwards, Rib muscles relax and move ribs down and inwards, Volume of the chest decreases, Lungs get smaller, Pressure in lungs is increased, Air flows out of the lungs
• Organs for gas exchange

  • Gills (e.g. fish)
  • Skin (e.g. frogs)
  • Stomata in leaves (plants)
  • Lungs
• Anaerobic respiration causes

  Muscles to tire quickly
• Carbon dioxide detection methods

  • limewater turns cloudy
  • an indicator (such as hydrogen carbonate) because it is acidic
• Chemicals in cigarette smoke

  • Nicotine
  • Tar
  • Carbon monoxide
  • High temperature of smoke
• Means, estimates and ranges

  Range = highest value – lowest value, Mean = number of values total of all values, Mean can be used to estimate a true value from repeated readings
• Aerobic respiration

  A series of chemical reactions that release energy
• Breathing in (inhalation)

  Diaphragm contracts and moves downwards, Rib muscles contract and lift ribs up and outwards, Volume of the chest increases, Lungs expand, Pressure in lungs is reduced, Air flows into the lungs
• Chemicals in cigarette smoke are harmful
• After strenuous exercise

  Body needs extra oxygen, EPOC replaces oxygen lost from stores and provides oxygen for increased levels of aerobic respiration
• Anaerobic respiration

  Does not require oxygen, releases less energy than aerobic respiration
• Anaerobic respiration

  glucose → lactic acid
• Lactic acid travels from muscles to liver


  Converted back to glucose
• Ventilation

  Movement of air into and out of the lungs
• Aerobic respiration

  glucose + oxygen → carbon dioxide + water
• Harm caused by cigarette smoke

  • Makes arteries narrower, causes heart disease
  • Can cause cancer, coats lungs reducing surface area, can cause alveoli to break apart (emphysema)
  • Stops red blood cells carrying so much oxygen
  • Stops cilia working so lungs are not cleaned and mucus collects
• When you exercise, your breathing rate and pulse rate increase because cells need more oxygen and glucose for respiration