Gas exchange in fish

Cards (23)

  • Why can't fish simply diffuse oxygen across their surface?
    They have a small surface area to volume ratio
  • What is the gas exchange surface in fish?
    The gills
  • How much less oxygen does water contain compared to air?
    30 times less oxygen
  • What are the three key features of every gas exchange surface?
    Large surface area, short diffusion distance, concentration gradient
  • What adaptations do fish gills have for gas exchange?
    • Large surface area due to gill filaments
    • Short diffusion distance from thin gill lamellae
    • Counter current flow to maintain concentration gradient
  • How is the rate of diffusion calculated in gas exchange?
    Using Fick's law
  • How many layers of gills do fish have on each side of their head?
    Four layers
  • What are the structures on the gills called that increase surface area?
    Gill filaments
  • How are gill lamellae positioned in relation to gill filaments?
    At right angles to the gill filaments
  • Where does gas exchange occur in fish gills?
    On the gill lamellae
  • What is the role of the capillary network in gill lamellae?
    It provides a short diffusion distance
  • What is the counter current flow in fish gills?
    Water flows opposite to blood in capillaries
  • Why is counter current flow advantageous for fish?
    It prevents equilibrium, maintaining diffusion
  • What happens in concurrent flow compared to counter current flow?
    Equilibrium is reached, stopping diffusion
  • What is the saturation level of water entering the gills?
    100% saturation with oxygen
  • How does the oxygen concentration change as water flows over the gills?
    It decreases from 100% to near 0%
  • What is the significance of maintaining a diffusion gradient in fish gills?
    It allows continuous oxygen uptake
  • What are the three features of gas exchange surfaces in fish?
    • Large surface area to volume ratio
    • Short diffusion distance
    • Mechanism to maintain concentration gradients
  • What is the advantage of counter current flow over concurrent flow?
    It maintains diffusion across the entire lamellae
  • What is the role of gill lamellae in fish gills?
    They facilitate gas exchange
  • What is the primary function of gills in fish?
    To facilitate gas exchange
  • How does the structure of gills contribute to their function?
    They provide a large surface area for diffusion
  • How does the design of gills prevent reaching equilibrium?
    Counter current flow keeps oxygen concentration gradient