What's the difference between archenteron and primitive?
Archenteron
Definition:
(n.) The primitive enteron or undifferentiated digestive sac of a gastrula or other embryo. See Illust. under Invagination.
Example Sentences:
(1) Several lines of experimental evidence indicate that contact with the animal pole locus, or "target" region, is crucial for the change in phenotype of the SMCs: (1) the phenotypic change can be induced precociously by bringing the animal pole region within reach of the tip of the archenteron early in gastrulation.
(2) Although some dorsoventral abnormalities are observed, animal-vegetal differentiation of the archenteron and associated structures seems largely normal, based on the localization of region-specific gene products.
(3) In view of the hypocalcaemic properties of calcitonin and the importance of calcium ions in cell aggregation, this phenomenon has been attributed to an alteration in cell adhesion which results in faulty cell migration during gastrulation with consequent abnormalities of the prechordal region of the archenteron roof and the overlying neural plate.
(4) Yolky tissue from the vegetal hemisphere of the gastrula or the archenteron floor of the neurula synthesized mainly polydisperse material of high molecular weight rather than discrete glycoproteins.
(5) We have investigated the mechanisms and specificity of this localization by analyzing filopodial behavior and by experimental manipulation of the interaction of the archenteron with the animal pole region.
(6) This study examines the mechanisms of epithelial cell rearrangement during archenteron elongation in the sea urchin embryo using scanning electron microscopy, differential interference contrast videomicroscopy, cell marking, and fluorescently labeled chimaeric clones.
(7) Marked somitic mesoderm disappeared from the superficial epithelial layer soon after passing over the blastoporal lip and could not be found on the archenteron surface.
(8) The results show a distinct anisotropic distribution of meridional and circumferential tensions, which are capable of producing the dynamics and shape of the archenteron development.
(9) Only in Cyclostomata all preotic segments are formed from the wall of archenteron and are larval segments.
(10) CyIIIa, only in the aboral ectoderm lineage; CyI, in the gut, oral ectoderm and some mesenchyme cells of plutei, and preferentially in the archenteron of gastrulae; M, only in two small clusters of cells near the esophagus in plutei).
(11) In nickel-treated embryos, the stomodeal invagination is expanded to become a circumferential constriction, and it eventually pinches off as the tip of the archenteron fuses with it to produce a mouth.
(12) The archenteron was composed of presumptive naupliar mesoderm and the blastopore was located at the site of the future anus of the nauplius larva.
(13) In light of subsequently discovered effects of colchicine on other cellular processes, the role of MTs in archenteron elongation in the sea urchin, Lytechinus pictus, has been reexamined.
(14) It has long been thought that traction exerted by filopodia of secondary mesenchyme cells (SMCs) is a sufficient mechanism to account for elongation of the archenteron during sea urchin gastrulation.
(15) The blastocoelar cells arise from mesenchyme released from the tip of the archenteron following the initial phase of gastrulation.
(16) Some labelled cells grafted to the anterior midline are found in the oral ectodermal lining, whereas cells from the archenteron are found in the notochord.
(17) Combinations were made between explants of mesoderm from the archenteron roof of early Xenopus neurulae and explants of ectoderm from mid-blastulae.
(18) When the tip of the archenteron nears the animal pole, some filopodia make contact with a well-defined locus within this region.
(19) The archenteron elongates and extends across the blastocoel until the tip of the archenteron touches and attaches to the opposite side of the blastocoel.
(20) During gastrulation, the antigen was localized in the cells lining the blastopore and in the extracellular space between the two cell layers, in the presumptive archenteron.
Primitive
Definition:
(a.) Of or pertaining to the beginning or origin, or to early times; original; primordial; primeval; first; as, primitive innocence; the primitive church.
(a.) Of or pertaining to a former time; old-fashioned; characterized by simplicity; as, a primitive style of dress.
(a.) Original; primary; radical; not derived; as, primitive verb in grammar.
(n.) An original or primary word; a word not derived from another; -- opposed to derivative.
Example Sentences:
(1) Cloacal exstrophy, centered on the maldevelopment of the primitive streak mesoderm and cloacal membrane, results in bladder and intestinal exstrophy, omphalocele, gender confusion, and hindgut deformity.
(2) Evx-1 RNA is first detected shortly before the onset of gastrulation in a region of ectoderm containing cells that will soon be found in the primitive streak.
(3) As an extension of the previous study which indicated that mesoglea is a primitive basement membrane which has retained some characteristics of interstitial extracellular matrix, the present study was undertaken to analyze the role of mesoglea components during head regeneration in Hydra vulgaris.
(4) neuroblastomas, primitive neuroectodermal tumours (PNETs), rhabdomyosarcomas and malignant lymphomas.
(5) We concluded that the primitive eukaryote D.discoideum contains proteins which show functional and physical similarity with the alpha-subunits of vertebrate G-proteins.
(6) Mechanisms are suggested whereby rudimentary appetitive programs already encoded along facing dendrite membrane pairs within the specialized intrafascicular milieu, may trigger and control nipple search and suckling in the still blind and only primitively mobile neonate.
(7) Thus, the progeny of infected primitive multipotential cells are competent to express integrated proviruses.
(8) Multiple tuberculomas have simulated either an alcoolic encephalopathy in one case or a primitive cerebral tumour in another one.
(9) This increased cell flow down the early stages of the red cell pathway in CML suggests that heightened proliferation and differentiation of primitive hemopoietic cells may be a more general phenomenon than previously suspected in this disease.
(10) The Lerner & Lerner Scale for assessing primitive defenses is reviewed.
(11) Only tumors of astrocytic lineage like astrocytomas and glioblastomas, or tumors of mixed lineage as oligo-astrocytomas and multipotential primitive neuroectodermal tumors (PNET) expressed TNF-alpha-like immunoreactivity.
(12) This epithelial cell was tentatively identified as primitive extraembryonic endoderm by its ultrastructural appearance and its possession of cytokeratin intermediate filaments.
(13) The long-term culture corresponded to mouse MXT and MCF-7 cell lines whereas the primary culture corresponded to primitive breast cancers squashed onto histologic slides and maintained in cultures for between 12 and 48 h. Cell proliferation was evaluated by means of digital cell image analysis of Feulgen-stained nuclei.
(14) From these facts, it was concluded that the follicular, as well as acanthomatous, ameloblastoma is liable to undergo squamous differentiation, whereas the plexiform ameloblastoma remains in primitive stage of tumor differentiation.
(15) A cluster of spermatogonia may be derived from one primitive germ cell and it develops round a "Sertoli" cell.
(16) Shielded marrow self renewal capacity, a measurement reflecting primitive hematopoietic stem cell function, remained depressed and did not recover with time.
(17) In a 3-year-old child, a rare combination of a Dandy-Walker syndrome, a primitive trigeminal artery and a facial haemangioma was found.
(18) As the histochemical and ultrastructural findings are non specific, we believe, according to recent opinions, that this tumor could originate in a very primitive cell, able to differentiate to endocrine or exocrine elements, almost always incompletely.
(19) It is likely that the development of these malignancies is an expression of the multipotential nature of primitive germ cells.
(20) Morphology of the mature spermatozoon is modified from that of the classic primitive or ect-aquasperm type by having 1) the acrosome embedded in the nucleus (the only known example within the Mollusca), 2) a deep basal invagination in the nucleus containing proximal and distal centrioles and an enveloping matrix (derived from the rootlet), 3) laterally displaced periaxonemal mitochondria, and 4) a tail extending from the basal invagination of the nucleus.