Which of the following statements is true about the intervillous space?
A - The blood in the intervillous space is in direct contact with embryonic trophoblast cells
B - It is not lined by endothelial cells
C - It is filled with maternal blood
D - The intervillous space is formed by the fusion of maternal blood vessels and spaces between fetal trophoblasts
E - All of these are true statements about the intervillus space
Answer: E - All of these are true statements
The blood-filled sinuses expand and the trophoblasts form finger-like structures called chorionic villi. These finger-like structures of the placenta composed of embryo-derived trophoblasts become surrounded by maternal blood in what is now called the INTERVILLUS SPACE.