| GVB | Germinal vesicle breakdown |
|---|---|
| EGL | external germinal layer |
| = GMH | germinal matrix hemorrhage |
| germinal localization | Determination in very young embryos of the presumptive areas for specific organs or structures. Synonym: fate map. (05 Mar 2000) |
|---|---|
| germinal membrane | In many eggs with a large amount of yolk, cell division (cleavage) is restricted to a superficial layer of the fertilized egg (meroblastic cleavage). This layer is termed the blastoderm. In birds it is a flat disc of cells at one pole of the egg and in insects an outer layer of cells surrounding the yolk mass. (18 Nov 1997) |
| germinal mutation | A mutation in the germ cells (the cells which will undergo meiosis to form the gametes). Such mutations are therefore passed on to offspring. (09 Oct 1997) |
| germinal pole | <cell biology> In most animal oocytes the nucleus is not centrally placed and its position can be used to define two poles. That nearest to the nucleus is the animal pole and the other is the vegetal pole, with the animal vegetal axis between the poles passing through the nucleus. During meiosis of the oocyte the polar bodies are expelled at animal pole. In many eggs there is also a graded distribution of substances along this axis, with pigment granules often concentrated in the animal half and yolk, where present, largely in the vegetal half. (12 Nov 1997) |
| germinal rod | One of the minute elongated bodies resulting from the repeated division of the oocyst during sporogony. In the case of the malarial parasite, it is the form that is concentrated in the salivary glands and introduced into the blood by the bite of a mosquito; it enters the liver cells (exoerythrocytic cycle), whose progeny, the merozoites, infect the red blood cells to initiate clinical malaria. Synonym: germinal rod, zoite, zygotoblast. Origin: sporo-+ G. Zoon, animal (05 Mar 2000) |
| germinal streak | An ectodermal ridge in the midline at the caudal end of the embryonic disk from which arises the intraembryonic mesoderm; achieved by inward and then lateral migration of cells; in human embryos, it appears on day 15 and gives a cephalocaudal axis to the developing embryo. Synonym: germinal streak. (05 Mar 2000) |
| germinal vesicle | The nucleus of a primary oocyte, the development of which is suspended in prophase I of the first meiotic division between embryohood and sexual maturity. (09 Oct 1997) |