(n.) The outer layer of the blastoderm; the ectoderm. See Blastoderm, Delamination.
Example Sentences:
(1) Expansion of the cell sheet following attachment, and the fusion of epiblasts advancing toward each other, does not require the presence of mineralocorticoid.
(2) At the midgastrula stage the epiblast cells have the highest dry weight due to the highest protein concentration in the cytoplasm and the biggest cell volume.
(3) Proliferation occurs throughout the extra-embryonic epiblast during the expansion period.
(4) These observations are consistent with an epiblast origin for the avian germ line, and are strikingly similar to those reported for the early mouse embryo using the same antibody (Hahnel & Eddy, 1986).
(5) IGFBP-2 mRNA was detected throughout the epiblast of the egg cylinder as early as e7, when IGF-II expression was restricted to trophectoderm and other extraembryonic cells.
(6) It is also noted that the inadequate differentiation of the epiblast and endoderm would not have been apparent without microscopic examination.
(7) Both X chromosomes continued to replicate synchronously in the embryonic ectoderm or epiblast at this stage.
(8) The resulting space is not homologous with the primordial amniotic cavity; instead, it is a transitory tropho-epiblastic cavity.
(9) After the yolk has been covered, the epiblast continues to grow, with proliferation restricted largely to band just distal to the advancing edge of the area vasculosa.
(10) Primordial germ cells in the mouse are known to be derived from the epiblast.
(11) In general, the dorsoventral orientation of the previously induced epiblast was retained, but the orientation of the competent epiblast cells was more flexible and could be influenced by the neighbouring neuralised cells.
(12) The results of this study show that the epiblast cells of chick blastoderm at Hamburger-Hamilton stage 1 contain macrobodies which themselves contain particles resembling the 'lining bodies' described by Bellairs.
(13) At one time presumed to be derived from a common "neural" ancestor, all are now deemed to be "neuroendocrine-programmed," arising either in the embryonic epiblast itself or in one of its principal descendants.
(14) Epiblastic cells never gave rise to skeletal myotubes.
(15) The definitive amniotic epithelium forms by the upfolding and mitotic proliferation of the margins of the epiblastic disc; this process is completed in 11-day rhesus, and 9-day human, blastocysts.
(16) At 108 h and 120 h pc the polar trophoblast (Rauber's layer) is an intact epithelium overlying the epiblast of the inner cell mass.
(17) The epiblast cells of the optic bud do not migrate into the brain and the lamina is formed by the proliferation of the central imaginal disc.
(18) By the time of primitive streak formation (stage 4-5) the dorsal surface of the epiblast displayed increased binding sites, while the frequency of sites on the ventral surface of the endoblast was reduced.
(19) A microinjection technique is described for fate mapping the epiblast of avian embryos.
(20) Injection in situ of a short-term lineage label (horse radish peroxidase) into single epiblast cells at 6.7 days p.c.
Periblast
Definition:
(a.) The protoplasmic matter which surrounds the entoblast, or cell nucleus, and undergoes segmentation.
Example Sentences:
(1) Specialized accumulations of membranes lie in the marginal periblast, and it is suggested that they play a role in cell membrane formation.
(2) The subgerminal periblast possesses a greater proportion of yolk to cytoplasm than do the cells proper, but it merges with the cytoplasm at the incomplete borders of the 'open' cells.
(3) (2) The periblastic region, which also exhibits microvillous projections, is 250-550 micron wide and consists of numerous (80-120) lacunae that are 10-60 micron in diameter and up to 20 micron in depth.
(4) (3) At the outer periblastic region, the microvillous projections are less numerous.