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Question 1
Which vessel carries the highest oxygen saturation in the fetus?
A) Umbilical arteries
B) Ductus venosus
C) Umbilical vein
D) Pulmonary artery
Correct Answer: C) Umbilical vein
Rationale: The umbilical vein carries oxygenated blood from
the placenta to the fetus (80–85% saturation). Umbilical
arteries carry deoxygenated blood to the placenta.
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Question 2
What is the primary function of fetal baroreceptors?
A) Detect pH changes
B) Detect blood pressure changes
C) Detect temperature changes
D) Detect oxygen changes
Correct Answer: B) Detect blood pressure changes
Rationale: Baroreceptors in the aortic arch and carotid sinuses
trigger vagal-mediated bradycardia with hypertension and
tachycardia with hypotension.
Question 3
Scenario: A 35-week fetus has episodic accelerations with
fetal movement. This indicates:
A) Fetal acidemia
B) Fetal well-being
C) Umbilical cord compression
D) Maternal fever
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Correct Answer: B) Fetal well-being
Rationale: Episodic accelerations with movement are a
reassuring sign of an intact central nervous system and
adequate oxygenation.
Question 4
Which part of the fetal nervous system predominantly controls
baseline heart rate?
A) Sympathetic nervous system
B) Parasympathetic nervous system (vagus)
C) Somatic nervous system
D) Enteric nervous system
Correct Answer: B) Parasympathetic nervous system
(vagus)
Rationale: The vagus nerve exerts dominant parasympathetic
tone, slowing the intrinsic heart rate. Sympathetic stimulation
increases rate.