changes at birth

Question 1

How does the mother support the foetus before birth?

Answer 1

Supplies O₂ and nutrients via placenta, removes CO₂ and wastes, regulates temperature, provides protection and immunity

Question 2

What is the ductus venosus?

Answer 2

Vessel bypassing liver, closes after birth

Question 3

What is the ductus arteriosus?

Answer 3

Lung bypass allowing blood from pulmonary artery to aorta; closes weeks after birth

Question 4

What is the foramen ovale?

Answer 4

Oval opening between atria, closes at birth (failure = ‘hole in heart’)

Question 5

What triggers the first breath at birth?

Answer 5

Shock or rise in CO₂

Question 6

What happens when the umbilical cord is clamped?

Answer 6

Blood rerouted, lungs and liver become functional

Question 7

What is a newborn’s heart rate?

Answer 7

125–130 bpm (up to 180 when excited)

Question 8

What is newborn breathing rate?

Answer 8

≈45 breaths/min, slows after 2 weeks

Question 9

How do blood cells change after birth?

Answer 9

RBCs increase, WBCs high then decrease after 7 days

Question 10

Summary of changes at birth?

Answer 10

Foetus transitions to independent circulation and breathing; bypass vessels close, lungs and liver become functional