Difference between revisions of "File:Placenta anchoring villi.jpg"

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==Placenta Anchoring Villi==
 
==Placenta Anchoring Villi==
  
Histological image showing the junctional region between the trophoblast shell of the conceptus and the maternal decidua.
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Histological image showing the junctional region between the maternal decidua (left) and the embryonic placental villi (right).
 
   
 
   
In week 2, the trophoblast shell cells proliferate and form a syncitiotrophoblast and cytotrophoblast layer around he conceptus. Syncitiotrophoblast cells migrate into the uterine wall, forming maternal blood-filled spaces (lacunae).
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* In week 2, the trophoblast shell cells proliferate and form a syncitiotrophoblast and cytotrophoblast layer around he conceptus.  
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* Syncitiotrophoblast cells migrate into the uterine wall, forming maternal blood-filled spaces (lacunae).
  
 
Placentation begins once the conceptus begins to implant in the uterine wall and the placenta will have both a fetal and a maternal component. The fetal component begins as villi form. The fetal chorion will form two regions: smooth chorion (chorion laeve) and villous chorion (chorion frondosum).
 
Placentation begins once the conceptus begins to implant in the uterine wall and the placenta will have both a fetal and a maternal component. The fetal component begins as villi form. The fetal chorion will form two regions: smooth chorion (chorion laeve) and villous chorion (chorion frondosum).

Revision as of 19:01, 23 May 2011

Placenta Anchoring Villi

Histological image showing the junctional region between the maternal decidua (left) and the embryonic placental villi (right).

  • In week 2, the trophoblast shell cells proliferate and form a syncitiotrophoblast and cytotrophoblast layer around he conceptus.
  • Syncitiotrophoblast cells migrate into the uterine wall, forming maternal blood-filled spaces (lacunae).

Placentation begins once the conceptus begins to implant in the uterine wall and the placenta will have both a fetal and a maternal component. The fetal component begins as villi form. The fetal chorion will form two regions: smooth chorion (chorion laeve) and villous chorion (chorion frondosum).

The maternal component is formed by the decidualization of the endometrium.

  • Fibrinoid layer (Nitabuch's layer) is formed at maternal/fetal interface during placentation and is thought to act to prevent excessively deep conceptus implantation.
    • Fibrin-type fibrinoid - maternal blood-clot product)
    • Matrix-type fibrinoid - secreted by invasive extravillous trophoblast cells


Placenta Links: placenta | Lecture - Placenta | Lecture Movie | Practical - Placenta | implantation | placental villi | trophoblast | maternal decidua | uterus | endocrine placenta | placental cord | placental membranes | placenta abnormalities | ectopic pregnancy | Stage 13 | Stage 22 | placenta histology | placenta vascular | blood vessel | cord stem cells | 2013 Meeting Presentation | Placenta Terms | Category:Placenta
Historic Embryology - Placenta 
1883 Embryonic Membranes | 1907 Development Atlas | 1909 | 1910 Textbook | 1917 Textbook | 1921 Textbook | 1921 Foetal Membranes |1921 human | 1921 Pig implantation | 1922 Single placental artery | 1923 Placenta Review | 1939 umbilical cord | 1943 human and monkey | 1944 chorionic villus and decidua parietalis | 1946 placenta ageing | 1960 first trimester placenta | 1960 monkey | 1972 Placental circulation | Historic Disclaimer

| Implantation


Image Source: UNSW Embryology, no reproduction without permission.

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current15:37, 3 August 2009Thumbnail for version as of 15:37, 3 August 2009600 × 450 (167 KB)MarkHill (talk | contribs)Placenta anchoring villi Histological image showing the junctional region between the trophoblast shell of the conceptus and the maternal decidua. In week 2, the trophoblast shell cells proliferate and form a syncitiotrophoblast and cytotrophoblast lay