Useful Study Notes on Placenta: Structure and Functions (Explained with Diagram) Structure: Placenta is a structure that establishes firm connection between the foetus and the mother. From the outer surface of the chorion a number of finger like projections known as chorionic villi grow into the tissue of the uterus. These villi penetrate the tissue of the uterine wall of [...]
Transformation of blastula or blastocyst into gastrula is called gastrulation. During gastrulation the cells of the inner cell mass of blastocyst or blastula move in small mass to their new final location. Such movement of cells is called morphogenetic movements Gastrulation results in the formation of three germ layers: ectoderm, mesoderm and endoderm. Each germ layer gives rise to specific [...]
In addition to the embryo proper, the blastoderm gives rise to certain other structures which lie outside the embryo. These are called as foetal membranes or extra embryonic membranes. These are essential for the complete development of the embryo. These include chorion, amnion, allantois and yolk sac. (i) Chorion: It completely surrounds the embryo and protects it. It consists of [...]