The structure that contains two arteries and one vein, and connects the developing embryo to the mother's body, is called the amnion placenta embryo umbilical cord

Umbilical cord is the correct answer to the fill in the blank.

Cell division is important to single celled organisms because it allows the cells to reproduce. through cell division, cells make exact copies of themselves. when single celled organisms go through cell division, they make exact copies of themselves which is how they reproduce.

Ithink its c hope it : )