blastoderm

American  

[blas-tuh-durm] / ˈblæs təˌdɜrm /

noun

Embryology.

1. the primitive layer of cells that results from the segmentation of the ovum.

2. the layer of cells forming the wall of the blastula, and in most vertebrates enclosing a cavity or a yolk mass.

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blastoderm British  

/ ˈblæstəʊˌdɜːm /

noun

1. the layer of cells that surrounds the blastocoel of a blastula

2. a flat disc of cells formed after cleavage in a heavily yolked egg, such as a bird's egg

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Other Word Forms

• blastodermatic adjective
• blastodermic adjective

Etymology

Origin of blastoderm

First recorded in 1855–60; blasto- + -derm

Example Sentences

Such words as "blastoderm", "sindoc," "peris," "parasang," "sarcenet," "teazel," "nullah," "cantatrice," "barracan," "sistrum," writhed and hissed in her verses.

From Time Magazine Archive

The rudimentary thorax presents traces of a division into three segments; and the dorso-lateral margins of the cephalic blastoderm, behind the procephalic lobes, have a sinuous margin.

From On the Origin and Metamorphoses of Insects by Lubbock, John, Sir

According to his account the cells of the blastoderm are formed actually in the ovum.

From Form and Function A Contribution to the History of Animal Morphology by E. S. (Edward Stuart) Russell

Pander observed the germinal membrane or blastoderm, as he for the first time called it, of the fowl’s egg to acquire three layers of organized substance in the earlier period of incubation.

From Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 3 "Electrostatics" to "Engis" by Various

Ventral plate: a thickening of the blastoderm of an egg from which the embryo, but not the amnion or serosa is formed.

From Explanation of Terms Used in Entomology by Smith, John. B.