epiblast

American  

[ep-uh-blast] / ˈɛp əˌblæst /

noun

Embryology.

1. the primordial outer layer of a young embryo before the segregation of the germ layers, capable of becoming the ectoderm and containing cells capable of becoming the mesoderm and endoderm.

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epiblast British  

/ ˈɛpɪˌblæst /

noun

1. Also called: ectoblast.  embryol the outermost layer of an embryo, which becomes the ectoderm at gastrulation

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Other Word Forms

• epiblastic adjective

Etymology

Origin of epiblast

First recorded in 1865–70; epi- + -blast

Example Sentences

The epiblast emits Nodal, while the lid, the extraembryonic endoderm, releases the counterpart BMP.

From Science Daily • Jun. 18, 2024

With this unprecedented clarity, the team directly observed two key moments in gastrulation: the first epiblast symmetry-breaking event and the emergence of the molecular markers of the primitive streak and mesoderm upon in vitro attachment.

From Science Daily • Mar. 23, 2024

Control cells clustered according to lineage and are indicated with the coloured bars: red, primitive endoderm; green, epiblast; and blue, trophectoderm.

From Nature • Sep. 19, 2017

Transcriptomics analysis revealed that, in POU5F1-null cells, gene expression was downregulated not only for extra-embryonic trophectoderm genes, such as CDX2, but also for regulators of the pluripotent epiblast, including NANOG.

From Nature • Sep. 19, 2017

The epiblast has been regarded as representing a second cotyledon, but this is a very doubtful interpretation.

From Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3 "Gordon, Lord George" to "Grasses" by Various