Question

Relating to the fetal circulatory system, which special characteristics allow the fetus to obtain sufficient oxygen from the maternal blood? (Select all that apply.)

a.Fetal hemoglobin (Hb) carries 20% to 30% more oxygen than maternal Hb.
b.Fetal Hb carries 40% to 50% more oxygen than maternal Hb.
c.Hb concentration is 50% higher than that of the mother.
d.Fetal heart rate is 110 to 160 beats per minute.
e.Fetal heart rate is 160 to 200 beats per minute.

Answer 1

The fetus obtains sufficient oxygen from the maternal blood through fetal hemoglobin, fetal heart rate, and umbilical arteries.

Step-by-step explanation:

The fetus obtains sufficient oxygen from the maternal blood through several special characteristics:

1. Fetal hemoglobin (Hb) carries 20% to 30% more oxygen than maternal Hb.
2. Fetal heart rate is 110 to 160 beats per minute, which ensures a steady flow of oxygenated blood.
3. Two umbilical arteries carry oxygen-depleted blood away from the fetus.

Fetal hemoglobin has a greater affinity for oxygen than adult hemoglobin, allowing the fetus to efficiently extract oxygen from maternal blood. The higher fetal heart rate helps deliver oxygen to the fetal tissues, compensating for the lower partial pressure of oxygen in the maternal blood. The umbilical arteries transport oxygen-depleted blood back to the placenta for reoxygenation.