human gas exchange

• label the lungs

  A) trachea

  B) bronchus

  C) bronchiole

  D) alveoli

  E) diaghram

  
• gas exchange in the alveoli

  • gas exchange occurs between the epithelium and blood
  • there are 300 million in each lung which increases surface area
  • alveoli epethelium cells are thin which provides a short diffusion path
  • theres a large network of capilliaries which provides a steep concentration gradient
• how do you calculate pulmonary ventilation rate ?

  tidal volume × breathing rate
• alveoli are tiny air filled sacks with one cell layer this...

  epethelial cells
• cappiliaries are one cell thick...

  endothelial cells
• How is a steep concentration gradient of oxygen and carbon dioxide maintained between the alveoli and capillaries

  • constant ventilation
  • good blood supply
• how do you Inhale?

  • the external intercolostal muscles contract
  • the diaphragm contracts
  • increased volume
  • decreased pressure
  • draws air in
• how do you exhale?

  • the internal intercolostal muscles contracts
  • the diaphragm relaxes
  • the volume decreases
  • pressure increases
  • air is forced out
• what does the thorax include

  • intercolostal muscles
  • rib cages
  • diaphragm
  • lung
• what occurs during normal quiet breathing g

  elastic tissues recoil
• how does gas exchange occur in the alveoli ?

  • oxygen diffuses down the conc gradient
  • across the alveolar epithelium
  • across the capillary endothelium
• endothelium is for

  blood vessels and lymph vessels
• epithelium is for

  organs and tissues