'''Collar cells''' are a flagellated [[cell|cells]] that pump water into a [[sponge]].<ref>Sponges feed by filtering small food particles (some even eat bacteria) out of water pumped through the system by flagellated collar cells. (See [http://www.reef.edu.au/asp_pages/secb.asp?FormNo=14 Sponges: Animals without Backbones])</ref>
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'''Collar cells''' are a flagellated [[cell]]s that pump water into a [[sponge]].<ref>Sponges feed by filtering small food particles (some even eat bacteria) out of water pumped through the system by flagellated collar cells. (See [http://www.reef.edu.au/asp_pages/secb.asp?FormNo=14 Sponges: Animals without Backbones])</ref>
<ref>Wile, Dr. Jay L. ''Exploring Creation With Biology''. Apologia Educational Ministries, Inc. 1998</ref>
<ref>Wile, Dr. Jay L. ''Exploring Creation With Biology''. Apologia Educational Ministries, Inc. 1998</ref>