trophoblast
Quick Summary
The trophoblast is the outer layer of cells in a mammalian blastocyst, a very early stage of embryonic development. It plays a crucial role in establishing a connection with the mother's uterus, facilitating implantation.12
About six to ten days after fertilization, the blastocyst, with its trophoblast layer, attaches to the uterine lining. The trophoblast then invades the uterine wall, enabling the developing embryo to become physiologically dependent on the mother. This process is essential for the formation of the placenta, which will nourish and support the embryo throughout pregnancy. The trophoblast's ability to invade and interact with the uterine tissue is key to a successful pregnancy.341
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blastocyst…now referred to as the trophoblast. It does not contribute directly to the formation of the embryo but rather serves to establish a connection with the maternal uterus. It is a precursor of the placenta.
Read More…now referred to as the trophoblast. It does not contribute directly to the formation of the embryo but rather serves to establish a connection with the maternal uterus. It is a precursor of the placenta.
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animal developmentAdaptations in mammals…of the morula become the trophoblast and the inner cell mass gives rise to the embryo (the formative cells) and also its yolk sac, amnion, and allantois. A cavity appears within the morula, converting it into a hollow embryo, called the blastocyst. This cavity resembles the blastocoel but, in fact,…
Read More…of the morula become the trophoblast and the inner cell mass gives rise to the embryo (the formative cells) and also its yolk sac, amnion, and allantois. A cavity appears within the morula, converting it into a hollow embryo, called the blastocyst. This cavity resembles the blastocoel but, in fact,…
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prenatal developmentCleavage and blastulation…segregated internal cluster, constitutes the trophoblast. It will contribute to the formation of a placenta and fetal membranes. During its stay within the uterine cavity, the blastocyst loses its gelatinous capsule, imbibes fluid, and expands to a diameter of 0.2 mm (0.008 inch); this is nearly twice the diameter of…
Read More…segregated internal cluster, constitutes the trophoblast. It will contribute to the formation of a placenta and fetal membranes. During its stay within the uterine cavity, the blastocyst loses its gelatinous capsule, imbibes fluid, and expands to a diameter of 0.2 mm (0.008 inch); this is nearly twice the diameter of…
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- pregnancyThe uterus and the development of the placenta
…cells; these cells are the trophoblast, which has a special ability to attach to and invade the uterine wall. The trophoblast plays an important role later in the development of the placenta or afterbirth. The conceptus makes contact with the uterine lining about the fifth or sixth day after conception.…
Read More…cells; these cells are the trophoblast, which has a special ability to attach to and invade the uterine wall. The trophoblast plays an important role later in the development of the placenta or afterbirth. The conceptus makes contact with the uterine lining about the fifth or sixth day after conception.…
Read More - pregnancyTrophoblastic disease
A hydatidiform mole is an abnormality of the conceptus in which changes that began early in embryonic life convert the placental villi into a mass of thin-walled, grapelike, translucent vesicles, or blisters, filled with a gelatinous or watery fluid. In a…
Read MoreA hydatidiform mole is an abnormality of the conceptus in which changes that began early in embryonic life convert the placental villi into a mass of thin-walled, grapelike, translucent vesicles, or blisters, filled with a gelatinous or watery fluid. In a…
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