'Germinal layers' definitions:

Definition of 'Germinal layers'

From: GCIDE
  • Germinal \Ger"mi*nal\, a. [See Germ.]
  • 1. Pertaining or belonging to a germ; as, the germinal vesicle. [1913 Webster]
  • 2. (Biol.) Of or pertaining to the germ, or germ cells, as distinguished from the somatic cells. [Webster 1913 Suppl.]
  • Germinal layers (Biol.), the two layers of cells, the ectoblast and entoblast, which form respectively the outer covering and inner wall of the gastrula. A third layer of cells, the mesoblast, which is formed later and lies between these two, is sometimes included.
  • Germinal membrane. (Biol.) Same as Blastoderm.
  • Germinal spot (Biol.), the nucleolus of the ovum.
  • Germinal vesicle, (Biol.), the nucleus of the ovum of animals. [1913 Webster]