Cleavage divisions differ from normal mitotic divisions in that

Identify $A, B, C$ and $D$ in the figure given below

The amniotic fluid is taken out with the help of surgical needle and separation of the embryo cells present in this fluid is done by

Which of the following decidua layer forms a partition between developing embryo and lumen at uterus?

The abdominal passage which connects the abdominal cavity with the scrotal sac in mammals is known as