Schematic drawing of inner anatomy of a teleost fish: 1 liver, 2 stomach, 3 intestine, 4 heart, 5 swim bladder, 6 kidney, 7 testicle, 8 ureter, 9 efferent duct, 10 urinary bladder, 11 gills
<a href="//commons.wikimedia.org/wiki/User:Uwe_Gille" title="User:Uwe Gille">Uwe Gille</a>
CC BY 2.5
<span class="int-own-work" lang="en">Own work</span>