germinal disk

American  

noun

Embryology.

1. blastodisk.

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Etymology

Origin of germinal disk

First recorded in 1875–80

Example Sentences

Segmentation is, as in other richly yolked eggs, incomplete, confined to the germinal disk at the opercular pole.

From Project Gutenberg

In this work, in the large folio form, beautiful representations are given of the author’s valuable observations on human embryology, and on that of various mammals, birds and fishes, and of the author’s 327 discovery in 1847 of the process of partial yolk segmentation in the germinal disk of the fowl’s egg during its descent through the oviduct, and his observations on the same phenomenon in fishes and mammals.

From Project Gutenberg

These "eating yelk-cells" are found in large numbers in the food-yelk of the Selachii, especially in the yelk-wall—the border zone of the germinal disk in which the embryonic vascular net is first developed.

From Project Gutenberg

Germinal disk. layers, the. scheme of the. spot, the. vesicle, the.

From Project Gutenberg

The circular border of the germinal disk which connects the roof and floor of the segmentation-cavity corresponds to the border-zone at the equator of the amphibian ovum.

From Project Gutenberg