In a human fetus, an opening remains between the left atrium and the right atrium of the heart. Shortly after birth this opening usually closes. When this opening does not close, the infant is called a “blue baby” because the skin has a bluish tint.
Which statement is true of an infant with this heart abnormality?
a. The level of oxyhemoglobin in the blood is too high.
b. Some deoxygenated blood enters the left side of the heart from the right side of the heart.
c. The opening causes an increase in systemic arterial blood pressure.
d. Some deoxygenated blood escapes from the pulmonary arteries into the pulmonary veins.