2.6 - Placenta and umbilical cord

Question 1

What does the placental organ develop from?

Answer 1

It develops from the trophoblast following implantation of the blastocyst into the uterine endometrium

Question 2

What is the purpose of the placenta?

Answer 2

Forms a link for physiological exchange between maternal and foetal circulation

Question 3

Describe the maternal side of the placenta

Answer 3

Disc shaped, rough and spongey

Question 4

Describe the foetal side of the placenta

Answer 4

Smooth and bears the attachment of the umbilical cord

Question 5

List four functions of the placenta

Answer 5

1. Gaseous exchange
2. Foetal waste
3. Supply of nutrients
4. Antibody supply

Question 6

When does the placenta physiologically separate from the uterine wall?

Answer 6

Third stage of labour after delivery of foetus

Question 7

How many umbilical arteries and veins are there?

Answer 7

2 arteries and 1 vein

Question 8

Function of umbilical arteries?

Answer 8

Provide deoxygenated blood from foetus to mother

Question 9

Function of umbilical vein?

Answer 9

Carry oxygenated blood from placenta to foetus

Question 10

Which umbilical vein persists during foetal circulation?

Answer 10

Left umbilical vein (right obliterates 4-7 weeks gestation)

Question 11

What does the left umbilical vein become after birth?

Answer 11

Ligamentum teres of liver

Question 12

What is the name of the gelatinous substance within the umbilical cord?

Answer 12

Wharton’s jelly