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The outermost layer of cells of the mammalian blastocyst that attaches the fertilized ovum to the uterine wall and serves as a nutritive pathway for the embryo.

tro′pho·blas′tic adj.


(Biology) 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]
ˌtrophoˈblastic adj


(ˈtrɒf əˌblæst, ˈtroʊ fə-)

the layer of extraembryonic ectoderm that nourishes the embryo or develops into fetal membranes with nutritive functions.
troph`o•blas′tic, adj.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.trophoblast - the membrane that forms the wall of the blastocyst in early development; aids implantation in the uterine wall; "after implantation of the blastocyst in the uterine wall the trophoblast divides into two layers, the chorion and the placenta"
blastosphere, blastula - early stage of an embryo produced by cleavage of an ovum; a liquid-filled sphere whose wall is composed of a single layer of cells; during this stage (about eight days after fertilization) implantation in the wall of the uterus occurs
tissue layer, membrane - a pliable sheet of tissue that covers or lines or connects the organs or cells of animals or plants
References in periodicals archive ?
Such factors as low content of progesterone or progesterone receptors deficit due to lower progesterone induced blocking factor might strengthen trophoblast apoptosis and suppression of its development (Sidelnikova and Suhih, 2003).
He did his research on "Placental Sulfoconjugated Estrogens in Cattle: By-products of Trophoblast Giant cell differentiation or Substrates of Pregnancy -Specific Sulfatase".
Control of expression of major histocompatibility complex genes in horse trophoblast.
It is to be expected that with cellular death and/or absence of development in the trophoblast, several secretory products would disappear, which could as well be inductors to the secretion of proteins by the uterus.
In this study, we used malignant UMR-106 osteosarcoma cells and normal HTRS/SVneo extravillous trophoblast cells, and found that simvastatin decreases cell viability, in a dose and time-dependent manner in both cell types.
Persistent trophoblast is detected by the failure of serum hcg levels to fall as expected after initial treatment, often a problem occurring after salpingotomy rather than salpingectomy.
Trophoblast origin of hCG isoforms: cytotrophoblasts are the primary source of choriocarcinoma-like hCG.
In situ localization of mRNA for the interferon, ovine trophoblast protein-1, during early embryonic development of the sheep.
Nick Gonzalez' book, The Trophoblast and the Origins of Cancer, which clarified and emphasized the relationship of the body's internal environment in the development and treatment of cancer, and highlighted, at least for us, the reasons the Gerson Therapy is so effective, so quick-acting and powerful in its reversal of all manner of chronic diseases.
The longest chapters in this collection describe clinical applications of human placental tissue, the dynamic role of trophoblast in placental development, insulin-like growth factors during pregnancy, and the activity of angiotensin II in the placenta.