The entire ectoderm arises from the first, second and third micromere quartets (collectively, the 'ectoblast').    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

This process goes on till all the cells are so filled by the mesoblast, with its myriad brood of cells, that the outer sac or ectoblast becomes a mere halo around it.    From Wordnik.com.  [The Atlantic Monthly, Volume 10, No. 61, November, 1862] Reference

In this form, he says, the progaster is already developed, and its wall is differentiated for the first time into an animal or dermal layer (ectoblast), and into a vegetative or intestinal layer (hypoblast).    From Wordnik.com.  [The Theories of Darwin and Their Relation to Philosophy, Religion, and Morality] Reference

When the mesoblast has become thus infinitely subdivided into hundreds of minute spheres, the ectoblast bursts, and the new generations of cells thus set free collect in that part of the egg where the embryonic disk is to arise.    From Wordnik.com.  [The Atlantic Monthly, Volume 10, No. 61, November, 1862] Reference

Oppositely, the vegetal extremities of the ectoblast.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

In each genus, some ectoblast tiers divide faster and others slower.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

(B) Normalized cell cycle lengths in later-formed ectoblast tiers of.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

(B) Schematic showing ontogeny of ectoblast cell distributions relative to the secondary axis.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

LR1, and that the progress of epiboly over the next three or four hours coincides with mitotic quiescence of the ectoblast.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

The mesoblast daughters of 4d meanwhile spread out underneath the ectoblast sheet; below this layer remain the nuclei of the.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

Soon after signaling from 3D / 4d, the form and timing of cell division begins to differentiate within most ectoblast tiers.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

This stage of development very shortly follows the complete transmission of an ectoblast patterning signal from the 3D / 4d cells.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

With the onset of epiboly, the ectoblast has become hemispherical, as reflected by the foreshortening of the 2a and 2c derivatives in this slightly dorsal view.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

The latest dividing cells among this group were consistently 3ab Cell numbers increase more or less linearly over time in the whole embryo and in the ectoblast.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

Two more rounds of division in the 4d lineage then mark well-defined 67-cell and 71-cell stages, collectively spanning a three-hour period during which the fifty-four ectoblast cells do not divide.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

In general, ectoblast cells form a cap on the surface of the embryo, sitting atop the large yolky macromeres; in early embryos, all of the ectoblast nuclei thus are found within a short focal distance.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

At early stages, oblique division axes generate a chiral, rotationally symmetric pattern; later, division axes within many ectoblast tiers show a collective bilateral symmetry and dorsoventral asymmetry.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

As epiboly proceeds, the ectoblast cap spreads out over the macromeres until it completely encloses them; at all times, ectodermal nuclei are distributed more or less evenly throughout this superficial cell sheet.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

The biologist could scarcely repress a burst of triumph as he perceived the germ gradually unfolding all the mysterious processes of mesoblast, ectoblast, and endoblast, which pertain to the earliest history of an arthropod.    From Wordnik.com.  [Renegade Futurist] Reference

The above described transformation of the spiral-cleaving embryo into a dorsoventrally polarized animal depends on an early intercellular signal that patterns the ectoblast along a secondary axis, orthogonal to the original (AV) axis of polarity.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

In other respects, the ectoblast of Ilyanassa displays the same rotational symmetry seen in other gastropod embryos (.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

Upper panels show a slightly earlier stage than (A), when ectoblast patterning is initiated by the 3D macromere (shown realistically in.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference

A substantial body of evidence suggests that the developmental program of each ectoblast micromere (or micromere daughter) is encoded combinatorially by its quartet / tier identity and its position relative to 3D / 4d (reviewed in.    From Wordnik.com.  [PLoS ONE Alerts: New Articles] Reference