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Placenta: 1st trimester
The composition of villi is demonstrated in an enlargement of floating chorionic villi located in the intervillous space. 400x
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Chorionic villi
The composition of villi is demonstrated in an enlargement of floating chorionic villi located in the intervillous space. 400x
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Embryonic connective tissue
The composition of villi is demonstrated in an enlargement of floating chorionic villi located in the intervillous space. 400x
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Cytotrophoblast
The composition of villi is demonstrated in an enlargement of floating chorionic villi located in the intervillous space. 400x
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Syncytiotrophoblast >
Syncytiotrophoblast is a single-cell syncytium that covers each villus and all chorionic surfaces, thus lining the intervillous space. This syncytium possesses abundant microvilli to increase surface area for transport. Syncytiotrophoblast synthesizes most of the placental hormones and is an important component of the barrier between fetal and maternal blood.
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- Microvilli
Syncytiotrophoblast is a single-cell syncytium that covers each villus and all chorionic surfaces, thus lining the intervillous space. This syncytium possesses abundant microvilli to increase surface area for transport. Syncytiotrophoblast synthesizes most of the placental hormones and is an important component of the barrier between fetal and maternal blood.