The Placenta and Umbilical Cord

Question 1

what does the placenta develop from?

Answer 1

Develops from the trophoblast following implantation of the blastocyst into the uterine endometrium.

Question 2

what is the function of the placenta?

Answer 2

It forms a link for physiological exchange between maternal and foetal circulation

Question 3

which is the foetal surface and which is the maternal surface of the placenta? why?

Answer 3

Foetal - smooth and bears the attachment of the umbilical cord
Maternal - disc-shaped and the structure is rough and spongy

Question 4

list four functions of the placenta

Answer 4

1. gaseous exchange
2. waste removal
3. providing nutrients
4. foetal protection

Question 5

at what stage of labour does the placenta physiologically separate from the uterine wall?

Answer 5

final stage of labour, third stage

Question 6

this is the cut-end of which structure? what can you see?

Answer 6

umbilical cord
- two umbilical arteries
- umbilical vein

Question 7

what is the function of umbilical arteries in the foetal circulation?

Answer 7

carry deoxygenated blood from foetal circulation to the placenta

Question 8

what structure (ligament) does the umbilical vein persist as in adult?

Answer 8

round ligament of liver

Question 9

what is the function of umbilical veins in the foetal circulation?

Answer 9

carry oxygenated blood from placenta to foetal circulation

Question 10

what is the structure labelled W in the cross-section?

Answer 10

Whorton’s jelly