Gill Structure of the Dogfish Shark


1.  Holobranch
2.  Parabranchial Gill Chamber
3.  Afferent Branchial Arteries
4.  Hemibranch
    The gills of the shark are lined on either side by gill filaments. These gill types are called holobranchs. The gills associated with the spiracle and sixth gill are hemibranchs because  gill filaments are found on one side only. An afferent branchial arteriole runs along the interbranchial septum. Numerous capillaries branch from this arteriole into the secondary lamella where air is exchanged.