(1) The fertilization reaction of echinoderm eggs (Lytechinus pictus, a sea urchin, and Dendraster excentricus, a sand dollar) was followed with intracellular electrodes.
(2) I describe the anatomy and fine structure of the echinoderm ovary, with emphasis on both the cellular relationships of the germ line cells to the somatic cells of the inner epithelium, and on the neuromuscular systems.
(3) In echinoderms, which stop at interphase, no such a factor has so far been found.
(4) In frogs and mammals, the oocytes are arrested at the second metaphase of meiosis whereas in echinoderms they are blocked later, at the pronucleus stage.
(5) An examination of Antp class homeo box genes in deuterostomes indicates that a chromosomal duplication has taken place in the evolutionary line leading to the vertebrates after the divergence of the echinoderms.
(6) Next, we present some features of the described processes for sugar and amino acid transport in the tubular portion of gastrointestinal tracts of three major invertebrate groups: echinoderms, molluscs, and arthropods.
(7) The emonctory structures, functions and stereotype and their component parts are studied in protists, spongia, coelenterata and coelomata: lower worms, annelids, their hyponeurian descendents (arthropods, molluses) and epineurian descedents echinoderms and protochordates (Stomochordata, Tunicata, Cephalochordata).
(8) The transition from the single creatine kinase locus, characteristic of certain echinoderms, to the two creatine kinase loci which are orthologous to those present in all vertebrates, occurred early in the chordate line.
(9) These features are characteristic of sea urchin (Echinoderm) spines which are composed of ornately formed calcite crystals covered by an epithelium.
(10) The echinoderms Asterias rubens and Solaster papposus (Class Asteroidea) metabolize injected [4(-14)C]cholest-5-en-3beta-ol to produce labelled 5alpha-cholestan-3beta-ol and 5alpha-cholest-7-en-3beta-ol.
(11) Echinoderm oocyte maturation is reviewed and a description of the ultrastructural, biochemical and molecular biological changes thought to occur during this process is presented.
(12) Another round of gene duplication, involving Wnt-3, -5, -7, and -10, occurred after the echinoderm lineage arose, on the ancestral lineage of jawed vertebrates.
(13) Changes in the distribution and organizational state of actin in the cortex of echinoderm eggs are believed to be important events following fertilization.
(14) Small numbers are present in algae, ferns, conifers, sponges, echinoderms, other marine animals, and arthropods.
(15) However, recent work which used colchicine to block microtubule assembly in the eggs of two other echinoderms, S. purpuratus and D. excentricus, has raised serious questions about the generality of this role for spindle microtubules.
(16) It would seem that these epitope regions have been strongly conserved since the epitope region is also present in the phosphoprotein of echinoderm teeth.
(17) Both species differences and species similarities in the agglutination were found in spermatozoa of the echinoderm, the sea urchin and the starfish.
(18) Furthermore, during meiotic maturation in these echinoderm and amphibian oocytes, this is followed by activation of many of the same protein-serine (threonine) kinases that are stimulated when quiescent mammalian somatic cells are prompted with mitogens to traverse from G0 to G1 phase.
(19) One of these fragments contains the active site and is identical at all sequenced residues with the corresponding region from the echinoderm sperm flagellar creatine kinase, and is 96% homologous with both chicken and rat B creatine kinase subunits.
(20) A significant feature of the early development of fertilized echinoderm and amphibian eggs and germinating seed embryos is the utilization of genetic information that has been previously transcribed during oogenesis and seed ripening.
Echinodermata
Definition:
(n. pl.) One of the grand divisions of the animal kingdom. By many writers it was formerly included in the Radiata.
Example Sentences:
(1) Twenty-two sterols were identified in the starfish Asterias rubens (Phylum, Echinodermata; Class, Asteroidea).
(2) (Echinodermata) and, for comparison, Mytilus edulis (Mollusca).
(3) Creatine was found in tissues of all vertebrates examined, and in various invertebrates from phyla Annelida, Echinodermata, Hemichordata and Chordata, subphylum Cephalochordata.
(4) Two peaks of arylsulphatase activity were detected biochemically in coelomocyte lysate preparations of seven different Echinodermata species.
(5) The Deuterostomia (the Hemichordata, Echinodermata and Chordata) evolved within the Bilateria by producing the mouth as a secondary perforation.
(6) S1 and S2 are the first neuropeptides identified in species belonging to the phylum Echinodermata.
(7) The degree of divergence of short and long repetitive DNA sequences and single copy DNA of five Echinodermata species (sea urchins, starfish, sea-cucumber) was studied by the method of molecular hybridization.
(8) The results obtained suggest that short repetitive DNA sequences are those which have been most highly conserved throughout the evolution of Echinodermata.
(9) Morphologic expressions resulting from nuclear transplantations between these two phyla (Echinodermata and Chordata) seemingly indicate functional interactions at a gene regulatory level.
(10) The studied AP displays a strong substrate inhibition, similar to that concerning Metazoa at a higher evolutionary level (Mollusca, Echinodermata).
(11) The results obtained suggest that short repetitive sequences were most conservative during the evolution of Echinodermata.
(12) The importance of the discovery of these cells in view of the biosynthesis of steroids and the phylogeny of Echinodermata is mentioned.
(13) By comparing environmental anaerobiosis with exercise anaerobiosis it appears that animals with high anoxia tolerance use (partly) different types of metabolic reactions to sustain energy metabolism, whereas low tolerance animals (Arthropoda, Echinodermata, Vertebrata) use the same pathway under both conditions.
(14) One or both of the two structural forms that exist, hydroxylysyl pyridinoline (HP) and lysyl pyridinoline (LP), was found in organisms from the following phyla: coelenterata, Annelida, Echinodermata, Mollusca and Arthropoda.
(15) Acrosin is widely distributed from Insecta to Echinodermata and Vertebrata; hyaluronidase has a similar diffusion, but seems to be absent from an Insect and from Echinodermata.
(16) The sea cucumber Paracaudina chilensis (Echinodermata) contains three major globins I, II and III in coelomic cells.
(17) Difference in the arrangement of single copy and repetitive sequences between Echinodermata species are not related to their evolutionary proximity.
(18) The Mollusca, Arthropoda, Echinodermata and Tunicata possess essentially the same features as the annelids.
(19) A similar contrast is found between cephalopoda and other mollusca, and the discussion of physiological adaptations is extended to include these groups and the Echinodermata.
(20) of the Platyhelminthes; Pomacea canaliculata, Aplysia kurodai, Bradybaena similaris and Achatina fulica of the Mollusca; and Gnorimosphaeroma rayi, Procambarus clarkii, Hemigrapsus sanguineus, Helice tridens and Gryllus bimaculatus of the Arthropoda; Asterina pectinifera of the Echinodermata; and Halocynthia roretzi of the Protochordata.