Blastocyst

The blastocyst is the initial stage of embryo development, at which it consists of a hollow cell vesicle with a thickening localized in it - the inner cell mass. It is from this thickening that the actual development of the embryo begins. The small cells of the blastocyst form the trophoblast, which will subsequently give rise to the outer layer of the membranes of the embryo.

At the initial stages, the blastocyst is not yet attached to any tissue, but later it is implanted into the wall of the uterus. The process of blastocyst implantation is an important step towards the formation of a full-fledged embryo.

Blastocyst is an early stage of embryo development, which is key for its further development and growth. At this stage, the embryo consists of a hollow cell vesicle that contains a thickening called the inner cell mass. It is from this mass that the development of the embryo then begins.

The small cells that surround the inner cell mass form the trophoblast. This layer of cells will later give rise to the outer layer of the membranes of the embryo. The trophoblast also plays an important role in the process of implantation of the blastocyst into the uterine wall.

At first, the blastocyst is not attached to anything and floats freely throughout the uterine cavity. However, it subsequently begins to attach to the wall of the uterus and is implanted into it. This process is called implantation and is an important stage in the development of the embryo.

Blastocyst implantation can occur at different times depending on many factors, including the age of the mother, the health and condition of the endometrium (the inner layer of the uterus), and the presence of any reproductive system diseases.

In conclusion, the blastocyst is an important stage in embryonic development and its understanding is of great importance for modern reproductive medicine. I hope this article has helped you better understand this stage of embryo development.

Topic of publication: Blastodermis blastocyte: the initial stage of embryonic development

**Introduction** The blastocyte is the initial stage of embryonic development and is derived from the extracellular mass of the germ cell by ingrowth of the inner cell mass (ICM) into the inner walls of the vesicular endocardium. Stem cells derived from primitive mesoderm differentiate into trophoblast-like structures that form the outer shell of the embryo. Subsequently, after the process of cell proliferation and migration, the germinal mass of the embryonic world is divided into a secondary cavity (retorsion area) and a trophoblast layer (exo-cellular), and is directly filled with dividing cells. This condition is characterized by the presence of a small number of eosinophils (trophic epithelial cells) and integumentary bodies. Trophoblastic cells then begin to migrate under the influence of a nutrient gradient (metabolic cycle) and form at two opposite poles an embryoblastic trophoblastic layer (climacroepithelium), consisting of biconcave pleonastons, which subsequently gives rise to embryonic mesohelium. Then large trophobals are formed, called “string of pearls”, which begin to form early embryonic membranes.