Question

What is the trophoblast?

Options

• A group of cells that develops into the embryo proper

• The outer layer of the blastocyst that helps in implantation and later forms the placenta

• The fluid-filled cavity inside the blastocyst

• The protective covering that disappears before implantation

Answer 1

The trophoblast is the outer cell layer of the blastocyst. It plays a crucial role in implantation by attaching to and eroding the endometrium. The trophoblast later develops into the placenta and other extraembryonic structures, while the inner cell mass develops into the embryo.