Question

Differentiate between the following:

Trophoectoderm and Ectoderm

Answer 1

Basis of Difference	Trophoectoderm	Ectoderm
Meaning	Trophoectoderm is another name for the trophoblast, the outer cell layer of the blastocyst.	Ectoderm is the outermost primary germ layer formed during gastrulation.
Developmental stage	Trophoectoderm is present at the blastocyst stage.	Ectoderm forms later, during gastrulation.
Relation to the embryo proper	Trophoectoderm does not form the embryo proper.	Ectoderm is part of the embryo proper.
Main functions	Trophoectoderm helps the blastocyst implant and contributes to the foetal part of the placenta.	Ectoderm gives rise to structures such as the skin, brain, spinal cord, and nerves.
Position	Trophoectoderm forms the outer layer of the blastocyst.	Ectoderm forms the outermost germ layer of the gastrula and developing embryo.