Apple QuickTime movie | 2003-04-17 | 4.0 MB | 256x192 | 15fps | 1 minute, 22 seconds
Transcription: Unlike land animals, almost all fish breathe or get their oxygen from water. Instead of using lungs, fish breathe with organs called gills. Most fish have four pairs of gills enclosed in a gill chamber on each side of the head. On the outside of the body, a flap of bone called a gill cover protects the gills of bony fish. To get oxygen, fish gulp water through the mouth and pump it over the gills. In many fish, The breathing process begins when the gill covers close and the mouth opens. The walls of the mouth then move inward. The mouth partially closes and the gill covers open. This action fo ...
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