Gas Exchange in Fish

• Where are gills located in fish?

  The mouth
• What is the Counter Current Exchange principle?

  Blood and oxygenated water moves over the gill in opposite directions

  • Fresh water comes into with the blood with the highest concentration of oxygen
  • Water with low oxygen concentration comes into contact with blood that has low oxygen

  In both cases oxygen is always diffusing into the blood
• What are Gill Filaments?

  Respiratory structures in fish
• What are Lamalla?

  Folds in Gill Filaments for increased Surface Area - absorption