What's the difference between planula and vesicle?
Planula
Definition:
(n.) In embryonic development, a vesicle filled with fluid, formed from the morula by the divergence of its cells in such a manner as to give rise to a central space, around which the cells arrange themselves as an envelope; an embryonic form intermediate between the morula and gastrula. Sometimes used as synonymous with gastrula.
(n.) The very young, free-swimming larva of the coelenterates. It usually has a flattened oval or oblong form, and is entirely covered with cilia.
Example Sentences:
(1) Adult specimens of Astrangia danae (Agassiz) and settled planulae of Porites porites (Pallas) contain crystals averaging 0.7 mu by 0.1 mu by 0.3 mu within Golgi-derived vesicles.
(2) Planulae processed with the SPG histofluorescence technique, specific only for catecholamines, exhibited blue-green fluorophores which were most prominent in the anterior ectoderm.
(3) Exposure of planulae to exogenous norepinephrine caused premature, rapid metamorphosis and produced polyps with slightly stunted tentacles and pitted, irregular hypostomes.
(4) Exposure of planulae to nicotine caused similar effects.
(5) RFamide antiserum bound a subset of ganglionic cells in the anterior and upper middle regions of the planula and a few ganglionic cells in the upper tail region.
(6) During gastrulation, the cnidocytes are Incorporated intO the ectoderm and become an integral part of the planula.
(7) Pretreatment of planulae with neuropharmacological agents which prevent reuptake (reserpine) or cause release (nicotine, ephedrine) of catecholamines caused a diminution of the fluorophores.
(8) The early embryonic development of Hydractinia lasts about 2.5 days until the developing planula larva acquires competence for metamorphosis.
(9) Using the same technique the reappearance of RFamide-positive ganglionic cells in epithelial tissue of chimeric grafts of planulae was observed.
(10) However, planulae raised in sea water containing propranolol, a beta blocker, ceased all movement, became tack-shaped and died within 72 h. These results meet multiple criteria for the identification of catecholamines in hydrozoan planulae and suggest that such catecholamines may function as neurotransmitters, neurohormones or neuromodulators during larval development.
(11) Ultrastructural examination of reserpine-treated planulae revealed a dramatic reduction in the populations of dense-cored vesicles and electron-dense droplets.
(12) Rearing planulae in sea water containing alpha blockers, phentolamine and tolazoline, had no discernible effect on behaviour (motility, phototactic response) or gross morphology.
(13) Planula larvae of Halocordyle disticha were examined for the presence of catecholamines using a multipronged approach.
(14) In non-metamorphosing planula larvae, PAF triggered the differentiation of nerve cells that normally develop only upon initiation of metamorphosis and that occur in the polyp stage.
(15) Stained repopulated ganglionic cells always formed in the same position in the epithelial tissue as was observed in control planulae suggesting that the expression of RFamide-like substances may be position dependent in the planula.
(16) A suggestion is put forward that at the final phase of larval development a special RNA is synthesized which participates in the genetically determined control of the complicated morphogenetic phenomenon of attachment and transformation of the planula in polyp.
Vesicle
Definition:
(n.) A bladderlike vessel; a membranous cavity; a cyst; a cell.
(n.) A small bladderlike body in the substance of vegetable, or upon the surface of a leaf.
(n.) A small, and more or less circular, elevation of the cuticle, containing a clear watery fluid.
(n.) A cavity or sac, especially one filled with fluid; as, the umbilical vesicle.
(n.) A small convex hollow prominence on the surface of a shell or a coral.
(n.) A small cavity, nearly spherical in form, and usually of the size of a pea or smaller, such as are common in some volcanic rocks. They are produced by the liberation of watery vapor in the molten mass.
Example Sentences:
(1) 5-HT thus appears to be the preferred substrate for uptake into platelets and for movement from cytoplasm to vesicles.
(2) The predicted non-Lorentzian line shapes and widths were found to be in good agreement with experimental results, indicating that the local orientational order (called "packing" by many workers) in the bilayers of small vesicles and in multilamellar membranes is substantially the same.
(3) Reasonably good agreement is seen between theoretical apparent rate-vesicle concentration relationships and those measured experimentally.
(4) In normal seminal vesicle, the reaction product was apparently more abundant in columnar and basal cells than in other cell types.
(5) Freshly isolated sarcoplasmic reticulum vesicles contain 0.05 mol of tightly bound ADP and 0.03 mol of tightly bound ATP per mol of Ca2+, Mg2+-ATPase (ATP phosphohydrolase, EC 3.6.1.3).
(6) In contrast, in primordial follicles, FSH was restricted to the germ cell but was present in both the oocyte cytoplasm and germinal vesicle.
(7) In fact, the distribution of [3H]oleate between plasma membranes and unilamellar vesicles of lipids extracted from these membranes was in favor of the lipids, indicating the absence of a detectable amount of binding to a putative fatty acid binding protein in plasma membranes.
(8) This value may be compared to a Kd of 7.3 pM obtained by the same method for the interaction of DF-VIIa with TF1-263 reconstituted into phosphatidylcholine vesicles.
(9) This is interpreted to be a consequence of the adsorption of Ca2+ on the vesicle bilayers.
(10) The results suggest that AH5183 does not bind to the ACh transporter recognition site on the outside of the vesicle membrane, and thus it might inhibit allosterically.
(11) Although the brain AP50 is prominently phosphorylated by an endogenous protein kinase in isolated coated vesicle preparations, the neuronal AP50 was not detectably phosphorylated in intact cells as assessed by two-dimensional non-equilibrium pH gradient gel electrophoresis of labeled cells dissolved directly in SDS-containing buffers.
(12) Interaction of viable macrophages with cationic particles at 37 degrees C resulted in their "internalization" within vesicles and coated pits and a closer apposition between many segments of plasmalemma than with neutral or anionic substances.
(13) The toxins preferentially attenuate a slow phase of KCl-evoked glutamate release which may be associated with synaptic vesicle mobilization.
(14) In vitro studies indicate that dendritic cells only process proteins for a short period of time, when the rate of synthesis of MHC products and content of acidic endocytic vesicles are high.
(15) The latter findings reinforce the concept that in pathologic states associated with cerebral oedema, pinocytotic vesicles fuse to form transendothelial channels which transport plasma proteins into brain.
(16) By contrast, techniques that involved collection of OM vesicles were successful in isolating OM of B. catarrhalis.
(17) It is thus probable that secondary lysosomes become part of the macrophage vesicle.
(18) The response is dose dependent for LPA concentrations from 10(-8) to 10(-3) M. Incubation of oocytes in LPA does not induce germinal vesicle breakdown.
(19) Caffeine and 6-methylaminopurine riboside (6-N-methyladenosine differentially inhibit uptake of radioactivity from adenosine and inosine, and thus the vesicles apparently possess seperate transport systems for uptake of radioactivity from purine nucleosides and from uridine.
(20) The mean length of the seminal vesicles was 2.98 cm.