The respiratory system, ventilation & gas exchange in humans

• what is the scientific name of the top part of your body?

  the thorax
• label these parts of the thorax

  A) trachea

  B) lung

  C) bronchus

  D) bronchiole

  E) aveoli

  F) pleural cavitiy

  G) intercostal muscle

  H) ribs

  I) diaphragm

  
• what happens when you breath in ?

  • intercostal muscles and diaphragm contract
  • thorax volume increases
  • decrease in pressure, air comes in
• what happens when you breath out ?

  • intercostal muscles and diaphragm relax
  • thorax volume decreases
  • pressure increases so air is forced out
• what are the features that all gas exchange surfaces have ?

  • large surface area
  • thin walls
  • good ventilation
  • good blood supply
• label this aveoli diagram

  A) oxygenated blood to heart

  B) deoxygenated blood from heart

  C) single alveolus

  D) large surface area to volume ratio

  
• label this aveoli diagram

  A) air in and out

  B) low oxygen

  C) low carbon dioxide

  D) good blood supply

  E) 1 cell thick for easy diffusion

  F) 1 cell thick for easy diffusion

  G) high carbon dioxide

  H) high oxygen

  
• what ilnesses does smoking cause ?

  • Lung cancer
  • heart disease
  • chronic obstructive pulmonary disease (COPD)
• what are the 3 chemicals in cigarettes ?

  • nicotine
  • tar
  • carbon monoxide
• what does nicotine do to your gas exchange system ?

  • narrows blood vessels leading to an increased blood pressure
  • increases heart rate
  • Both of these effects can cause blood clots to form in the arteries leading to heart attack or stroke
• what does tar do to your gas exchange system ?

  • increases chance of cancerous cells developing in lungs
  • can cause chronic bronchitis and emphysema
• what does carbon monoxide do to your gas exchange system ?

  • binds to haemoglobin so reduces capacity of blood to carry oxygen
  • gives risk of coronary heart disease and a stroke