Linked Life Data

15837957

Source:http://linkedlifedata.com/resource/pubmed/id/15837957

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2005-4-19
pubmed:abstractText
Cryptasterina hystera has a highly derived life history with intragonadal development and juveniles that emerge from the parent's reproductive tract. The gonads are ovotestes with developing eggs separated from sperm by follicle cells. C. hystera has typical echinosperm that must enter the gonoduct of conspecifics to achieve fertilization. During oogenesis, an initial period of yolk accumulation is followed by hypertrophic lipid deposition, the major contributor to the increase in egg size. 1-Methyladenine induces egg maturation and ovulation, but the spawning component of the hormonal cascade is suppressed. This is the major alteration in reproduction associated with evolution of viviparity in C. hystera. The switch to viviparity was not accompanied by major change in gonad structure, indicating there were few or no anatomical constraints for evolution of a marsupial function for the gonad. Despite their intragonadal habitat, the brachiolaria are equipped for a planktonic life, swimming in gonadal fluid. During the gastrula stage, lipid provisions are released into the blastocoel where they are stored for juvenile development. The eggs of C. hystera have light and dark cytoplasmic regions that mark animal-vegetal polarity. The dark pigment provided a marker to follow the fate of vegetal cells. Live birth is rare in the Echinodermata and the incidence of this form of brooding in the phylum is reviewed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-3185
pubmed:author
pubmed:issnType
Print
pubmed:volume
208
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
81-91
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Viviparity in the sea star Cryptasterina hystera (Asterinidae)--conserved and modified features in reproduction and development.
pubmed:affiliation
Department of Anatomy and Histology, F13, University of Sydney, NSW 2006, Australia. mbyrne@anatomy.usyd.edu.au
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't