What are the types of chorionic villi?

What are the types of chorionic villi?

At the end of pregnancy, six types of villi can be found in the placenta: stem villi, tertiary mesenchymatous villi, immature intermediate villi, mature intermediate villi, terminal or free villi, and trophoblast buds.

Where do the chorionic villi develop?

In the placenta, chorionic villi develop to maximize surface-area contact with the maternal blood for nutrient and gas exchange.

What is villi and trophoblast?

Villi attached to the maternal tissues via the trophoblastic shell are called stem or anchoring villi. Villi that grow from the sides of the stem villi are called branch villi, and it is through these that the major exchange of materials between the mother and the embryo takes place.

How are villi formed?

Villi formation occurs by the invagination of the mesenchymal cells that underlie the luminal epithelia, a process that follows the anterior–posterior wave of epithelial reorganization. These mesenchymal cells condense under the basal lamina and grow in fingerlike projections toward the lumen giving rise to the villi.

What is secondary chorionic villi?

Secondary chorionic villi have a core of loose connective tissue, which grows into the primary villi about the third week of development. Tertiary chorionic villi contain embryonic blood vessels that develop from mesenchymal cells in the loose connective tissue core.

Is placental villi and chorionic villi same?

…the placenta are known as chorionic villi. Chorionic villi make up a significant portion of the placenta and serve primarily to increase the surface area by which products from the maternal blood are made available to the fetus.

What do chorionic villi turn into?

Branches of the umbilical arteries carry embryonic blood to the villi. After circulating through the capillaries of the villi, blood returns to the embryo through the umbilical vein. Thus, villi are part of the border between maternal and fetal blood during pregnancy….

What is primary secondary and tertiary villi?

What is villi function?

Villi are tiny, finger-like projections from the wall of the small intestine. They line the inner surface of the small intestine. Their role is to increase the surface area within the small intestine. This will lead to the increase of the surface area of absorption as it is the main function of the small intestine.

What is primary chorionic villi?

Chorionic villi are villi that sprout from the chorion in order to give a maximum area of contact with the maternal blood. Embryonic blood is carried to the villi by the branches of the umbilical arteries, and after circulating through the capillaries of the villi, is returned to the embryo by the umbilical veins.

What is villi miscarriage?

In early miscarriage, the finding of chorionic villi in vaginal expulsions is often the only definite confirmation that there was an intrauterine pregnancy rather than an ectopic pregnancy.

What is tertiary villi?

Tertiary chorionic villi contain embryonic blood vessels that develop from mesenchymal cells in the loose connective tissue core. These blood vessels connect up with vessels that develop in the chorion and connecting stalk and begin to circulate embryonic blood about the third week of development.

What are paneth cells?

Paneth cells are highly specialized secretory epithelial cells located in the small intestinal crypts of Lieberkühn. The dense granules produced by Paneth cells contain an abundance of antimicrobial peptides and immunomodulating proteins that function to regulate the composition of the intestinal flora.

How do villi absorb food?

Villi that line the walls of the small intestine absorb nutrients into capillaries of the circulatory system and lacteals of the lymphatic system. Villi contain capillary beds, as well as lymphatic vessels called lacteals. Fatty acids absorbed from broken-down chyme pass into the lacteals.

What is the most important function of villi in small intestine?

absorption of nutrients
The structure of the small intestine is designed for absorption of nutrients. The inside of the small intestine is lined with villi that absorb nutrients from the liquid mixture called chyme produced in the stomach from the food we eat.