(1) Protoscolices isolated from sheep cysts grew in vitro in the polyzoic direction up to the three- to four-segmented mature worms, reaching a length of 2.9 mm.
Zooid
Definition:
(a.) Pertaining to, or resembling, an animal.
(n.) An organic body or cell having locomotion, as a spermatic cell or spermatozooid.
(n.) An animal in one of its inferior stages of development, as one of the intermediate forms in alternate generation.
(n.) One of the individual animals in a composite group, as of Anthozoa, Hydroidea, and Bryozoa; -- sometimes restricted to those individuals in which the mouth and digestive organs are not developed.
Example Sentences:
(1) 5-HT antigenicity in the postpharyngeal commissure indicates the initiation of the development of a new zooid.
(2) At the onset of takeover (T = 3 hr), B3F12.9 immunostaining became diffuse or absent at the anterior end, which paralleled the axis of contraction of the dying zooid, whereas the posterior end retained its labeling integrity.
(3) The latter process is similar to the degeneration of old individuals, or zooids, that precedes maturation of each new generation of asexual buds.
(4) The rate of cell fission was retarded in colchicine-containing media, but nevertheless short-stalked colonies with apparently normal zooids were formed.
(5) Site-specific reactions were also observed in larval tail muscle and the siphon muscles of postmetamorphic zooids.
(6) Here we describe a monoclonal antibody (B3F12.9) that recognizes a novel 57 Kd polypeptide (under reducing conditions) localized to the perivisceral extracellular matrix (PVEM) of buds and zooids, as well as blood cells of Botryllus by immunofluorescence and immunogold labeling of tissue sections.
(7) Here we describe comparisons of in vitro reactions of a) mixtures of cells from allogeneic animals and b) cells taken from animals at the zooid-resorption ("takeover") stage of colony development.
(8) Botryllus schlosseri is a colonial ascidian whose asexually derived, clonally modular systems of zooids exhibit developmental synchrony.
(9) The capsule of the dormant bud has some structural features in common with the black stolon of the adult zooids.
(10) A second impulse was recorded from individual zooids, probably generated by the polypide's nervous system.
(11) The colonial tunicate Botryllus schlosseri undergoes cyclic blastogenesis where feeding zooids are senescened and resorbed and a new generation of zooids takes over the colony.
(12) They form the probable route of transfer of yolk from the zooids to the dormant bud.
(13) These findings indicate that takeover is a dynamic process in which extracellular matrix breakdown proceeds in a polarized fashion, beginning at the anterior end of each zooid and gradually propagating toward the posterior end.
(14) In many attributes, these various junctions are more similar to those found in the tissues of vertebrates, than to those in the invertebrates, which the adult zooid forms of these lowly chordates resemble anatomically.
(15) The neoblast and mitosis distributions in the daughter zooid during its asexual reproduction cycle duplicate those observed in the maternal zooid.
(16) No larvae metamorphosed into oozooids with situs inversus viscerum, but in this study two oozooids extruded blastozooids showing this anomaly; these blastozooids budded "reversed" zooids in turn, so that entire clonal lines showed the anomaly.
(17) Under 2,000 rads some of the irradiated zooids within this type of union started to regenerate, and at 1,000 rads no resorption was recorded, even though the number of zooids decreased in the irradiated part.
(18) During their active feeding phase, zooids exhibited a uniform labeling pattern of PVEM along their anteroposterior (A-P) axis.
(19) With doses of 3,000-4,000 rads and above, irradiation arrested the formation of new buds and interrupted normal takeover, turning the colony into a chaotic bulk of vessels, buds, and zooid segments.
(20) During the first few days after fission, the number of neoblasts decreases in the portion of the body immediately adjoining the site of daughter zooid detachment and considerably increases in the regenerative bud.