Later Development, Develop. Physiol., Dr. D. Penney

Self-Assessment - Module 22: (Cont.)

    8. Maternal blood volume expands during gestation by smaller increases in red cell volume than plasma volume ( T / F )

    9. Dilation of the pulmonary arteriolar vessels, fall in pulmonary vascular resistance, and decline in pulmonary arterial blood pressure immediately following the newborn taking the first few breaths are due to a process of smooth muscle atrophy. ( T / F )

    10. Muscle fiber to capillary ratio in the heart declines after birth, until in adulthood this ratio approaches 1.0. ( T / F )

    11. Plasma 2,3-DPG concentration increases after birth, ( decreasing / increasing ) hemoglobins' affinity for oxygen

    12. The following changes occur during the perinatal period, except:

    1. increase in oxygen carrying capacity and hemoglobin after birth
    2. rise in systemic vascular resistance and pressure
    3. closure of the ductus venosus, ductus arteriosus and foramen ovale
    4. increase in arterial PO2 and percent hemoglobin saturation at birth
    5. gradual decrease in cardiac output and oxygen consumption on a per g body weight basis

    13. The reason the P50 of fetal blood is lower than that of adult blood is because:

    1. fetal blood contains practically no 2,3-DPG
    2. 2,3-DPG does not affect the affinity of fetal hemoglobin for oxygen
    3. both of the above

    14. Within minutes after birth, the hemoglobin is almost entirely of the adult (i.e. HbA) type. ( T / F )


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