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3 Cards in this Set
- Front
- Back
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How are the Gills Adapted for Effective Gas Exchange in Water? |
1) Large Surface Area 2) Rich Blood Supply to Maintain Steep Concentration Gradients 3) Thin Layers so Diffusion Distance is Short 4) Tips of Adjacent Gill Filaments Overlap - Increases resistance to flow of water over gills - Slows down movement of water - More time for gas exchange to occur 5) Countercurrent Exchange System - Ensures steeper concentration gradient is maintained - More gas exchange can take place. |
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Countercurrent Flow System |
1) Blood and water flow in opposite directions. 2) Oxygen concentration gradient between water and blood maintained along gill. 3) Oxygen continues to diffuse down concentration gradient. 4) Much higher level of oxygen saturation of blood is achieved. |
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Features of Specialised Exchange Surfaces |
1) Increased Surface Area 2) Thin Layers 3) Good Blood Supply 4) Ventilation to Maintain Diffusion Gradient |
