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| | ===Gills=== | | ===Gills=== |
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| | + | Gills are in the walls of both sides of the pharynx and are composed of filaments which increase the surface area. |
| | + | When a fish breaths, it takes in water into the mouth, which is then forced out through the gills. |
| | + | |
| | + | A '''Countercurrent Exchange''' system is in place within the gills to make gaseous exchange more efficient. |
| | | | |
| | ==Amphibia== | | ==Amphibia== |