A-Level Biology

Gas Exchange in Bony Fish

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.