(1) Because ctenophore and all other known metazoan mtDNA is circular, the shared occurrence of linear mtDNA in three of the four cnidarian classes suggests a basal position for the Anthozoa within the phylum.
(2) Cloning of three Antennapedia-related sequences from cnidarians provides evidence of ancient roles for homeobox genes early in metazoan evolution.
(3) Cnidocytes, the stinging cells of cnidarians, discharge nematocysts in response to physical contact accompanied by the stimulation of specific chemoreceptors.
(4) It is suggested that they may also be present as predominant components in nematocysts of other cnidarian species and thus might represent a class of compounds which is characteristic for a whole phylum of the animal kingdom.
(5) The principal sources of these agents are bacteria, higher fungi, cnidarians (coelenterates) and the venoms of snakes, insects and other arthropods.
(6) The presence of cholecystokinin (CCK), originally isolated from porcine small intestine, has been reported in a diversity of invertebrates ranging, from cnidarians to protochordates, but so far, not in echinoderms.
(7) Cnidarians arose from a protist ancestry different from the second group, the Bilateria.
(8) In these trees, cnidarians (Radiata) seemed to have evolved independently from the Bilateria, which is in contradiction with the general evolutionary view.
(9) It is present in all cnidarians and can be isolated without enzyme treatment.
(10) The ganglion has been compared to the nervous systems in cnidarians, some spiralians, and especially other hemichordates, echinoderms, and chordates; it is found to be of primitive rather than degenerate nature.
(11) We report the nucleotide sequence of eveC, a cnidarian eve-class homeobox; this is the first homeobox to be identified in any diploblastic organism, and is only the second eve-class in an invertebrate.
(12) We previously characterized annexin XII from the freshwater cnidarian Hydra vulgaris (Schlaepfer, D. D., D. A. Fisher, M. E. Brandt, H. R. Bode, J. Jones, and H. T. Haigler.
(13) This report describes the cloning and sequencing of both cDNA and genomic clones of GFP from the cnidarian, Aequorea victoria.
(14) Eggs from all of the animals considered are covered by complex vitelline envelopes except those of cnidarians.
(15) The application of molecular techniques to cnidarians can provide important insights into developmental processes and phylogenetic relationships both within the phylum Cnidaria and among the eumetazoa.
(16) A new system is described for the study of ECM-tissue interactions, using the ECM (called mesogloea) of various cnidarians and isolated striated muscle and endodermal tissue of jellyfish.
(17) gamma-Glutamyltransferase activity was studied in extracts of the cnidarian Hydra attenuata.
(18) The results show that: polyps under normal conditions have similar regeneration patterns, regardless of individual variability; and ATxII, a neurotoxin of cnidarian origin, produces a statistically significant increase in the Tentacle Regeneration Index.
(19) In the context of earlier observations in cnidarians, these cytological features suggest a sensory as well as a modulatory function for 5-HT in Renilla koellikeri.
(20) Specifically, sperm eggs from cnidarians, echinoderms, decapod crustaceans, ascidians, lampreys, bony fishes, and amphibians are discussed.
Invertebrate
Definition:
(a.) Destitute of a backbone; having no vertebrae; of or pertaining to the Invertebrata.
(n.) One of the Invertebrata.
Example Sentences:
(1) The results suggest that normal development of some invertebrate neural pathways may be more dependent on experience during ontogeny than has previously been assumed.
(2) This result is in contrast to most other animals (ranging from invertebrates to mammals), in which sperm are generally motile for at least several hours.
(3) This invertebrate precipitin, Tridacnin, may be used as a marker for nearly two thirds of all asialo serum glycoproteins; A number of different cross-reactions with various other polysaccharides and galactans subdivides those neuraminidase-treated glycoproteins into several subgroups, indicating that the uncovered carbohydrate structures are not always completely identical.
(4) We compared the molecular nature of the rat brain opiate receptor with that of the invertebrate leech, Haemopis marmorata, and the protozoan, Tetrahymena, in order to examine the issue of apparent receptor heterogeneity with respect to biochemical structure.
(5) The ruthenium red method was also used on a number of marine invertebrate embryos and larvae, representing different phyla, to facilitate comparisons between their surface coats.
(6) Using an SDS gel electrophoresis method, connectin, very high molecular weight (approximately 10(6) dalton) protein, was detected in an SDS extract of whole tissues of various types of muscles of vertebrates and invertebrates.
(7) Thirty-five antisera to 20 vertebrate regulatory peptides and 1 invertebrate peptide (FMRFamide) were used to screen the worm for neuropeptide IR.
(8) Purification procedures that appear to be generally applicable to invertebrate MTs have only recently been developed and are described here.
(9) The over-all response of duck erythrocytes is considered as an example of "isosmotic intracellular regulation," a term used to describe a form of volume regulation common to euryhaline invertebrates which is achieved by adjusting the number of effective intracellular osmotic particles.
(10) The body wall muscle and the blood vessel muscle are compared with other muscle types described in invertebrates.
(11) Although neither protein bound to heparin, gelatin, hexosamine, or uronic acid-Sepharose resins, their affinity for an invertebrate proteoglycan, their roles in sponge cell adhesion, and their peripheral membrane protein natures suggest that they may represent early invertebrate analogs of cell-associated vertebrate extracellular matrix adhesion proteins, such as fibronectin or vitronectin, or else an entirely novel set of cell adhesion molecules.
(12) In organisms as diverse as bacteria, plants, invertebrates, and vertebrates, synthesis of these proteins is directly correlated with the acquisition of thermotolerance.
(13) Invertebrate systems have proved to be quite useful for the development of an understanding of some processes in the central nervous system (CNS).
(14) The amino acid composition of the ABRM calmodulin closely resembled that of other invertebrate calmodulins.
(15) Current thinking on fixed behaviors in invertebrates holds that they are generated by specialized neural circuits in the brain.
(16) In view of reports that the nerve fibers of the sea prawn conduct impulses more rapidly than other invertebrate nerves and look like myelinated vertebrate nerves in the light microscope, prawn nerve fibers were studied with the electron microscope.
(17) To test the hypothesis that inositol trisphosphate (InsP3) mediates adaptation and excitation in invertebrate photoreceptors, we measured its formation on a rapid time scale in squid retinas.
(18) The cellular and circuit properties of individual identified neurons in invertebrates can be readily studied; hence it is possible to determine how the complex properties of nerve cells function in the generation of behavior.
(19) These processes may be conserved in a wide range of invertebrates and vertebrates.
(20) The action of ocular screening pigments of vertebrates (melanins) as well as those of invertebrates (ommochromes) on lipid peroxidation has been studied.