The effects of heavy metals on the asexual reproduction of the annelid Aeolosoma headleyi Beddard (1888)

dc.contributor.authorNewman, James Prestonen
dc.contributor.committeechairBuikema, Arthur L. Jr.en
dc.contributor.committeememberCairns, John Jr.en
dc.contributor.committeememberHolt, Perry C.en
dc.contributor.departmentZoologyen
dc.date.accessioned2014-03-14T21:36:47Zen
dc.date.adate2010-06-02en
dc.date.available2014-03-14T21:36:47Zen
dc.date.issued1975-06-03en
dc.date.rdate2010-06-02en
dc.date.sdate2010-06-02en
dc.description.abstractChronic bioassays were conducted on the annelid Aeolosoma headleyi Beddard (l888) to determine the effects of heavy metals on asexual reproduction. Bioassays were conducted with the chloride and sulfate salts of zinc, copper, cadmium, cobalt, and nickel. Additionally, chromium, as potassium dichromate, was tested. Of these metals, only two, zinc chloride and copper sulfate, significantly stimulated reproduction at or below 0.01 ppm of the metal. All metals inhibited reproduction at high concentrations and none, except the two above, had any significant effect on reproduction at the sublethal concentrations tested. Hydrogen ion concentrations between 6 and 10 units had no effect on reproduction. The effects of the metals were not due to pH or osmotic effects. Subsequent studies were conducted with zinc chloride to determine its effect on zooid scissiparity. As zinc concentrations increase, the time for first zooid scissiparity decreased. Second bud formation was inhibited by zinc levels greater than 0.1 ppm. Normally the worm exhibits paratomy (release of zooid with a developed cephalic region). Above 7.0 ppm zinc, the worms also exhibit architomy where the cephalic region is not developed prior to scissiparity.en
dc.description.degreeMaster of Scienceen
dc.format.extentvii, 82 leavesen
dc.format.mediumBTDen
dc.format.mimetypeapplication/pdfen
dc.identifier.otheretd-06022010-020200en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-06022010-020200/en
dc.identifier.urihttp://hdl.handle.net/10919/42839en
dc.publisherVirginia Techen
dc.relation.haspartLD5655.V855_1975.N445.pdfen
dc.relation.isformatofOCLC# 39019765en
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectheavy metalsen
dc.subjectasexual reproductionen
dc.subject.lccLD5655.V855 1975.N445en
dc.titleThe effects of heavy metals on the asexual reproduction of the annelid Aeolosoma headleyi Beddard (1888)en
dc.typeThesisen
dc.type.dcmitypeTexten
thesis.degree.disciplineZoologyen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen
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