in (Wood"s Hole, Mass,) .
Written in English
From Biological bulletin, 71.
|Other titles||Biological bulletin.|
|The Physical Object|
|Number of Pages||58|
The germinal vesicle (GV) is the nucleus of the oocyte (Figs. 1 B and 2 B). The GV is large and spherical and contains chromatin (DNA) and the nucleolus (Figs. 1 B and 2 B). The oocyte chromatin is located throughout the GV, and its exact configuration depends on the transcriptional activity of the oocyte as described further in the section. A preliminary study has also been made of the free germinal vesicle of this egg. The vesicles can be secured within about eight minutes after shedding, by placing the eggs in distilled water. Waterman AJ () The membranes and germinal vesicles of the. egg of Sabellaria vulgaris. Biol Bull – Wolstenho lme JK () Te . Egg yolk: It is formed by the ovary, and its formation is independent of fecundation. It is constituted of the white yolk, yellow yolk, and germinal disc. These are surrounded by the vitelline membrane. 2. Egg white: It surrounds the egg yolk and is constituted of three layers of different thicknesses.
the membranes and germinal vesicle of the egg of sabellaria vulgaris. a. j. waterman. 71(1), pp. 46– abstract | pdf ( kb) | permissions. The germinal vesicle is the nucleus of an oocyte that is arrested in prophase of meiosis I. The nuclear envelope of the germinal vesicle will break down in a process known as germinal vesicle break down (GVBD) when the oocyte resumes meiosis in response to the luteinizing hormone (LH) surge that occurs prior to ovulation. Germinal vesicle breakdown in mouse oocytes The first indication of germinal vesicle breakdown is the appearance of undulations in the nuclear envelope (Fig. 3), which can be seen in the earliest oocytes (fixed as early as 8 min after liberation from the follicle). Occasionally, microtubules appear to be directed toward the NE. The ‘vitelline membrane’ of the fully developed egg was found to consist of a layer of peri-vitelline material beneath which were two closely opposed unit membranes. The origin of these layers was discussed. The permeability of the shell and vitelline membrane was studied using simple physical techniques and radiotracers.
The large nucleus of the amphibian oocyte. This nucleus contains the three eukaryotic RNA polymerases and can also transcribe exogenous (microinjected) DNA. The oocyte then translates the mRNAs into a. Abstract. In this chapter we summarize data showing that sperm acrosomal protein activates Urechis eggs, causing a fertilization potential and morphological changes like those produced by sperm. We then review the evidence in Urechis that Ca 2+ uptake and acid release at fertilization cause rises in intracellular Ca 2+ and pH necessary for activation, and propose that both ion . Germinal vesicle definition, the large, vesicular nucleus of an ovum before the polar bodies are formed. See more. AND FERTILIZATION IN SABELLARIA VULGARIS A. J. WATERMAN (From the Department of Biology, Brooklyn College,1 and the Marine Biological The germinal vesicle is a large, vesicular, whitish area more or less eccentrically located. As seen under the microscope, the membrane of the egg of Echinarachnius and Asterias, which quickly.