The zona pellucida, a thick layer of extracellular matrix that surrounds the egg and is similar to the role of the vitelline membrane in sea urchins, binds with the sperm.
32.
The fourth hypothesis was commonly accepted, but it was later shown that the right vitelline artery ( right omphalomesenteric artery ) did not supply the anterior abdominal wall in this area.
33.
The first envelope-the one in contact with the membrane of the egg-is made of glycoproteins and is known as the vitelline membrane ( zona pellucida in mammals ).
34.
The inside of each mature proglottid is filled with muscular layers and complete male and female reproductive systems, including the tubular unbranched uterus, ovary, genital pore, testes, and vitelline gland.
35.
Furthermore, it can be attached to the umbilical region by the vitelline ligament, with the possibility of vitelline cysts, or even a patent vitelline canal forming a vitelline fistula when the umbilical cord is cut.
36.
Furthermore, it can be attached to the umbilical region by the vitelline ligament, with the possibility of vitelline cysts, or even a patent vitelline canal forming a vitelline fistula when the umbilical cord is cut.
37.
Furthermore, it can be attached to the umbilical region by the vitelline ligament, with the possibility of vitelline cysts, or even a patent vitelline canal forming a vitelline fistula when the umbilical cord is cut.
38.
Furthermore, it can be attached to the umbilical region by the vitelline ligament, with the possibility of vitelline cysts, or even a patent vitelline canal forming a vitelline fistula when the umbilical cord is cut.
39.
Blood is conveyed to the wall of the yolk sac by the primitive aorta, and after circulating through a wide-meshed capillary plexus, is returned by the vitelline veins to the tubular heart of the embryo.
40.
2 ) Diffusion must occur in a confined space, if a gradient is to be established however many organisms such as the axolotl develop normally even if the vitelline membrane and jelly layers are removed and development occurs in flowing water.
