BIO MARTIN 1

• Ventilation


  A process of taking in oxygen and releasing carbon dioxide through breathing
• Gas Exchange


  Oxygen is taken in from the environment and carbon dioxide is removed through the skin, gills, or lungs
• Transport


  Oxygen is transported from the lungs to the body's tissues via the blood circulatory system
• Cellular Metabolism


  In the mitochondria, oxygen is consumed, and carbon dioxide and ATP energy are produced through aerobic cellular metabolism
• Respiration includes four distinct processes concerned with acquiring oxygen (O2 ) and transforming it to energy:


  ventilation (air or water), gas exchange, and transport of gas between respiratory organs and tissue, cellular metabolism.
• Why might water be a problem as a respiratory medium?

  low oxygen content, high density and viscosity
• does colder water or warmer water have a higher oxygen content?

  colder
• The 3 different gas exchange mechanisms in water?

  Cutaneous diffusion only (body surface, skin), Cutaneous diffusion plus circulatory system (blood) , Gills plus circulatory system
• Cutaneous diffusion only:


  ...
• Ficks law (the rate of diffusion of oxygen)


  = Ko2 .A . ΔP/d
• To maximise oxygen uptake:

  maximise area, maximise partial pressure, minimise thickness
• gas exchange in flatworms occurs:

  via cutaneous diffusion