Final answer:
The embryonic membrane includes the yolk sac, placenta, allantois, chorion, and amnion, each serving distinct functions in fetal development. The yolk sac provides nutrients, placenta manages nutrient and waste exchange, allantois is involved in early fluid exchange, chorion envelops other membranes and contributes to placental development, and amnion forms a protective sac filled with fluid around the embryo.
Step-by-step explanation:
Embryonic Membranes and Their Functions
The embryonic membrane contains several structures critical for the development of an embryo. Among these are the yolk sac, placenta, allantois, chorion, and amnion. Each plays a unique role in embryogenesis:
- The yolk sac is essential early on for nutrient transfer and blood cell formation.
- The placenta is developed from the chorion and allantois, handling nutrient transport, gas exchange, and waste management between mother and fetus.
- The allantois contributes to early fluid exchange and eventually forms part of the umbilical cord.
- The chorion surrounds all other membranes and is involved in the growth and development of the placenta.
- The amnion creates the amniotic sac filled with fluid that protects the embryo and allows for its free movement.
The excluded option from the given list is not mentioned in the provided context.