A Level Biology Revision "Gas Exchange in Bony Fish" 

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In this video, we look at gas exchange in bony fish. First we explore the structure of the gills, including the gill arches, gill filaments and gill lamellae. We then look at how the structure of the gill lamellae are adapted for efficient diffusion of gases. We then explore how the gill lamellae use a counter-current exchange system to increase the rate of diffusion. Finally, we look at how bony fish maintain a constant water flow over their gills.
This video is aimed at the UK A Level Biology specifications. Students studying International A Level Biology will need to check their specification.
Image Credits:
Tuna
commons.wikimedia.org/wiki/Fi...
Stephane-bdc, CC BY-SA 4.0 creativecommons.org/licenses/..., via Wikimedia Commons
Salmon
commons.wikimedia.org/wiki/Fi...
Hans-Petter Fjeld, CC BY-SA 2.5 creativecommons.org/licenses/..., via Wikimedia Commons
Cod
commons.wikimedia.org/wiki/Fi...
Hans-Petter Fjeld, CC BY-SA 2.5 creativecommons.org/licenses/..., via Wikimedia Commons
Trout
commons.wikimedia.org/wiki/Fi...
Public domain
Carp with missing operculum
commons.wikimedia.org/wiki/Fi...
Guitardude012, CC BY 3.0 creativecommons.org/licenses/..., via Wikimedia Commons
Tuna gills
commons.wikimedia.org/wiki/Fi...
Chris 73 creativecommons.org/licenses/...
Gill Arches
commons.wikimedia.org/wiki/Fi...
User:Uwe Gille, CC BY-SA 3.0 creativecommons.org/licenses/b..., via Wikimedia Commons