Phascolosoma Agassizii Research Articles

The Annual Reproductive Cycle of the Sipunculid Phascolosoma agassizii

Previous articleNext article No AccessThe Annual Reproductive Cycle of the Sipunculid Phascolosoma agassiziiAlbert Towle and Arthur C. GieseAlbert Towle Search for more articles by this author and Arthur C. Giese Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Volume 40, Number 3Jul., 1967 Article DOIhttps://doi.org/10.1086/physzool.40.3.30152860 Views: 1Total views on this site Citations: 7Citations are reported from Crossref Journal History This article was published in Physiological Zoology (1928-1998), which is continued by Physiological and Biochemical Zoology (1999-present). Copyright 1967 University of ChicagoPDF download Crossref reports the following articles citing this article:A. Amor Reproductive cycle of Golfingia margaritacea, a bipolar sipunculan, in subantarctic water, Marine Biology 117, no.33 (Nov 1993): 409–414.https://doi.org/10.1007/BF00349316P. E. Gibbs Gametogenesis and spawning in a hermaphroditic population of Golfingia minuta (Sipuncula), Journal of the Marine Biological Association of the United Kingdom 55, no.11 (May 2009): 69–82.https://doi.org/10.1017/S0025315400015757Mary E. Rice SIPUNCULA, (Jan 1975): 67–127.https://doi.org/10.1016/B978-0-12-282502-6.50009-1Arthur C. Giese, John S. Pearse INTRODUCTION: GENERAL PRINCIPLES, (Jan 1974): 1–49.https://doi.org/10.1016/B978-0-12-282501-9.50006-5Lorry C. Oglesby Inorganic Components and Metabolism; Ionic and Osmotic Regulation: Annelida, Sipuncula, and Echiura, (Jan 1969): 211–310.https://doi.org/10.1016/B978-0-12-395537-1.50015-4Larry C. Oglesby Some osmotic responses of the sipunculid worm Themiste dyscritum, Comparative Biochemistry and Physiology 26, no.11 (Jul 1968): 155–177.https://doi.org/10.1016/0010-406X(68)90323-XA Towle, A.C Giese Biochemical changes during reproduction and starvation in the sipunculid worm Phascolosoma agassizii, Comparative Biochemistry and Physiology 19, no.44 (Dec 1966): 667–680.https://doi.org/10.1016/0010-406X(66)90424-5

Biochemical changes during reproduction and starvation in the sipunculid worm Phascolosoma agassizii

1. 1. Levels (% dry weight) of protein, non-protein nitrogen, total carbohydrate, glycogen, lipid and lipid fractions, and water were determined for Phascolosoma, some of them at various times in the reproductive cycle, and after various degrees of starvation. 2. 2. The body of the worm contains about 82·3 per cent water; various tissues contain 75–78 per cent water. The water content of a starved worm increases to between 86·2 and 88·3 per cent. 3. 3. The protein tissue (Kjeldahl) level is about 30 per cent; lipid levels vary for different tissues, being 25 per cent in the gut, 17·2 per cent for eggs, 6·9 per cent for sperms, and lesser quantities in muscle and body wall. However, the lipid level of the female body wall is double that of the male. About half of the lipid content of the female worm is in the eggs. 4. 4. Starvation results in a weight loss accompanied by a decrease in lipid reserves, particularly of the neutral lipid. Later the protein content also decreases. GLycogen levels are maintained or may even rise during starvation, although glycogen content may decline. Non-protein nitrogen levels rise during utilization of protein. 5. 5. The respiratory rate of Phascolosoma is of the order found in other marine invertebrates. Calculations based on oxygen consumption show that a Phascolosoma rapidly exhausts its nutrient reserves.