Explanation

Nourishment. The The trophoblast encircles the blastocoel and inner mass cell. The inner mass cell is the precursor of the embryo. It means that inner mass give rise to embryo. The cells of the trophoblast helps to provide the nutrition to the embryo. The cells of the trophoblast form extra embryonic membranes namely chorion and amnion. The cells of the trophoblast which are in contact with inner mass are called cells of raubers [image:3_image88.png]