The yolk sac functions to form blood cells in early development. provide nutrients to the fetus when the umbilical cord is disconnected. store metabolic wastes until the fetus is born. give rise to the primary germ layers.
The yolk sac functions to form blood cells in early development (embryonic phase) for nourishment of the embryo and early fetus. Towards the end of the 1st trimester, the yolk sac disappears and the placenta takes over for the fetus.
