A sheath of [[tissue]] that encloses the vital [[organ]]s of a [[mollusk]], makes the mollusk's shell, and performs [[respiration]].<ref>Wile, Dr. Jay L. ''Exploring Creation With Biology''. Apologia Educational Ministries, Inc. 1998</ref> | A sheath of [[tissue]] that encloses the vital [[organ]]s of a [[mollusk]], makes the mollusk's shell, and performs [[respiration]].<ref>Wile, Dr. Jay L. ''Exploring Creation With Biology''. Apologia Educational Ministries, Inc. 1998</ref> |