B6

• Aerobic Respiration : C6H12O6 + 6O2 → 6CO2 + 6H2O
• Anaerobic Respiration : Glucose -> Lactic Acid
• Anaerobic Respiration -> Ethanol + Carbon Dioxide
• %of O2 in inhaled air : 21
• %of O2 in exhaled air : 16
• %of CO2 in inhaled air : 0.04
• %of CO2 in exhaled air : 4
• %of N2 in inhaled air : 79
• %of N2 in exhaled air : 79
• Alveoli have a large surface area and capillaries
• Ventilation is the process by which fresh air enters the lungs through inspiration (inhalation) and stale air leaves the lungs through expiration (exhalation).
• Gas exchange occurs at the level of the alveolus, where oxygen diffuses from the alveolar space into the bloodstream and carbon dioxide diffuses out of the bloodstream into the alveolar space.
• Respiration: The chemical reactions that break down nutrient molecules (e.g. glucose) in living cells to release energy in the form of ATP.
• respiration is a chemical process, which takes place in every cell. Breathing is a mechanical process, which facilitates gaseous exchange in the lungs.
• Aerobic Respiration: A series of chemical reactions that break down nutrient molecules (e.g. glucose) in living cells in the presence of oxygen to produce relatively large amounts of energy.
• The body goes into anaerobic respiration producing lactic acid (which is harmful to the body). The body requires a steady supply of oxygen to break down the lactic acid (oxygen debt). The body continues a higher rate and depth of breathing to get this oxygen. Breathing will return to normal once all the lactic acid is broken down (oxygen debt is paid).        
• Anaerobic respiration is therefore defined as the chemical reactions that break down nutrient molecules (e.g. glucose) in living cells in the absence of oxygen to produce relatively small amounts of energy. 
• Lung Diagram

  A) Intercostal Muscles

  B) Heart

  C) Ribs

  D) Diaphragm

  E) Alveoli

  F) Bronchioles

  G) Bronchi

  H) Trachea

  
• The epiglottis is a flap that forms over the entrance of the trachea, which prevents food and other foreign substances from entering the air pipe.        
•  the trachea, bronchi and bronchioles all contain cartilage
• Cartilage keeps ariways open
• Human lungs:

  Large surface area – a large number of alveoli and shape of alveoli increase the surface area

  Thin or short distance – the lining of alveoli and capillaries are one cell thick

  Moist – the lining of the breathing system and alveoli kept moist with mucus. Cells die if not kept moist

  Good transport system – good supply of blood vessels 
• Oxygen constantly diffuses from the blood into the tissues, to be used as a raw material for cellular respiration in individual cells.
• Mucus forms a physical barrier between the surfaces of the gas exchange system and the pathogens and foreign particles.
• The cilia work together with the mucus. The cilia create beating motions which cause the mucus above it to move away from the alveoli, which in turn causes any pathogens or foreign particles to be expelled from the gas exchange system.
• Smoking paralyses Cillia. The mucus stops moving away from the alveoli. Gravity causes the mucus and dirt to move down and settle in the alveoli thereby reducing space for the exchange of gases.
• Oxygen can only be transported by the haemoglobin in red blood cells. If the haemoglobin is permanently bonded with carbon monoxide, there will be no way of transporting oxygen.
• Tar causes heart disease
• Nicotine is addictive
• Tar causes cancer
• Tumours occur when cells mutate and divide and grow excessively in the body. Normally, cell growth and division is strictly controlled.
• Carbon monoxide combines permanently with haemoglobin
• Nose or mouth → pharynx → larynx → epiglottis → trachea → bronchi → bronchioles → alveoli
• During exercise our muscles need more energy
• This energy is obtained during respiration
• Increasing respiration rate

  1. Cells must receive more glucose and oxygen from the bloodstream

  2. The additional oxygen will be obtained by increasing the rate of gas exchange in the lungs

  3. To bring in extra oxygen, we breathe deeper and faster
• After exercise is over

  The breathing rate returns to normal
• If anaerobic respiration occurred during exercise, extra oxygen, in addition to that needed for respiration of body cells, must be provided to remove the lactic acid
• Repaying the oxygen debt

  Providing extra oxygen to remove lactic acid produced during anaerobic respiration
• Aerobic vs Anaerobic labelling

  A) Requires Glucose

  B) Requires Glucose

  C) Requires Oxygen

  D) Doesnt require oxygen

  E) Produces a high yield of energy

  F) Produces a low yield of energy

  G) Produces Carbon Dioxide and Water in all cells

  H) Produces lactic acid in animal cell

  I) Produces Carbon Dioxide and Ethanol in yeast cells

  J) Produces Energy

  K) Produces Energy