- the layer of extraembryonic ectoderm that chiefly nourishes the embryo or develops into fetal membranes with nutritive functions.
Origin of trophoblast
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- the outer layer of cells of the embryo of placental mammals, which is attached to the uterus wall and absorbs nourishment from the uterine fluids
C19: from tropho- + -blast
- The outermost layer of cells of the blastocyst that attaches the fertilized ovum to the uterine wall and serves as a nutritive pathway for the embryo.trophoderm
- The outermost layer of cells of the blastocyst, which attaches the fertilized ovum to the uterine wall and serves as a nutritive pathway for the embryo. The trophoblast eventually differentiates into such tissues as the amnion, the placenta, and the umbilical cord.
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