A. Cantains two umbilical veins.
B. Contains one umbilical artery.
C. Right umbilical vein disappears.
D. Length is 25-30 cm.
The structure marked by an arrow in the picture above represents Umbilical cord.
- Umbilical cord develops from connecting stalk, which extends from the caudal end of the embryo to the chorion.
- Umbilical cord is covered by amniotic epithelium and contains a core of mesenchyme known as whartan’s jelly.
- Contents of umbilical cord are : (i) Wharton’s jelly, (ii) Two umbilical arteries, (iii) One (left) umbilical vein, (iv)Remnant of yolk sac, and (v) Remnant of allanto-enteric diverticulum.
- Initially 2 umbilical arteries and 2 umbilical veins develop in mesoderm, but right umbilical vein disappears. Left umbilical vein persists along with 2 umbilical arteries.
- At full term, the umbilical cord measures 1-2cm in diameter, and 50-55cm in length and generally attached to the center of fetal surface of placenta.