Which extraembryonic membrane lines the chorion and contains the fetus and amniotic fluid?

Which extraembryonic membrane lines the chorion and contains the fetus and amniotic fluid?

• A. Amnion
• B. Yolk sac
• C. Chorion
• D. Allantois

Answer: (A)

Amnion lines the inner surface of the chorion and forms the amniotic cavity that surrounds the fetus with amniotic fluid. This membrane develops from the fetal ectoderm with extraembryonic mesoderm and stays just inside the chorion, creating a protective sac around the developing baby. The amniotic fluid cushions the fetus, permits movement, and helps regulate temperature. The chorion is the outer membrane that contributes to the placenta, the yolk sac provides early nutrients and blood cells, and the allantois is involved in waste storage and the development of the umbilical cord.

Amnion lines the inner surface of the chorion and forms the amniotic cavity that surrounds the fetus with amniotic fluid. This membrane develops from the fetal ectoderm with extraembryonic mesoderm and stays just inside the chorion, creating a protective sac around the developing baby. The amniotic fluid cushions the fetus, permits movement, and helps regulate temperature. The chorion is the outer membrane that contributes to the placenta, the yolk sac provides early nutrients and blood cells, and the allantois is involved in waste storage and the development of the umbilical cord.