Question 4
What is the placenta formed from?
The right answer is the one marked above.
The amniotic membranes of the foetus joining the inner wall of the uterus. Both sides contribute — that is what makes it the meeting place of two circulations.
The umbilical cord is a separate structure that connects the placenta to the foetus; it carries an artery and a vein. Neither the uterine wall nor the morula forms a placenta on its own.