Fetal Circulation

Which organ systems in the fetus are nonfunctional?

respiratory digestive urinary lymphatic

1. What organ provides for their functions before birth?

Placenta

1. Which blood vessel takes red blood from the umbilical vein to the inferior vena cava?

1. Ductus

Venosus

List the two bypasses of the lungs.

foreman

ovale

ductus

arteriosus

How many umbilical arteries are there?

2

They branch off from what other arteries?

1. internal iliac arteries

1. Do the umbilical arteries carry red, mixed, or "blue" blood?

Mixed

How many vessels are in the umbilical cord?

3

Is lung compliance high or low during the first breaths?

Low

Does this mean the first breaths are easy or difficult?

Especially difficult

Before birth, the pressure in the right atrium is higher than in the left atrium. After birth, which side has higher pressure?

Left atrium

What happens at birth because of this pressure change?

Closer of foramen oval

What causes the ductus arteriosus to close?

Higher O2 availability causes it to constrict

what does the ductus arteriosus become after birth

ligamentum arteriosum

What does the umbilical vein become?

Round ligament