The protective sac around the embryo or fetus is the amniotic sac.
The Amniotic Sac
The amniotic sac is the sac in which the fetus develops in amniotes. Its wall is the amnion, the inner of the two fetal membranes. It encloses the amniotic cavity and the embryo.
amniotic sac
Amniotic membrane or amniotic sac, containing the embryo and amniotic fluid.
In the first developmental stage of the embryo, you have the ball of cells. In this ball of cells you have cavity filled with fluid called amniotic fluid. This fluid sac separates the embryo, from the outer non-embryo cells. Later on it encloses the fetus in amniotic fluid to give amniotic sac. This sac is attached to uterus from inside.
Amniotic sac
Amniotic sac
amniotic sac :)
amniotic sac
There is no such thing as an "ovarian sac". The amnion is a membrane building the "amniotic sac" that surrounds and protects an embryo.
Amniotic fluid is a nourishing fluid found in the amniotic sac of the embryo. Its main function is nourishment of the embryo. Please refer to the related questions for detailed information on Amniotic fluid.