Pregnancy and birth Knowledge-Based Practice

Questions

1. 1.

   In the mature human placenta, how does the exchange of respiratory gases and nutrients take place between maternal and fetal circulations?

   • A) Maternal and fetal blood mix directly within shared vascular chambers across the uterine wall.
   • B) Maternal blood enters the fetal umbilical vein directly through open channels in the placenta.
   • C) Substances diffuse across the tissues of chorionic villi that separate maternal blood in intervillous spaces from fetal capillary blood.
   • D) Maternal red blood cells are actively engulfed by fetal trophoblast cells to release bound oxygen into fetal vessels.
2. 2.

   During human childbirth, the process of labor is divided into three distinct physiological stages. Which event specifically characterizes the first stage of labor?

   • A) The detachment and expulsion of the placenta and attached fetal membranes
   • B) The progressive effacement and dilation of the cervix to approximately ten centimeters
   • C) The passage and final delivery of the fetus through the birth canal
   • D) The rapid postpartum involution of the uterine wall to prevent hemorrhage
3. 3.

   Which of the following correctly describes the anatomical arrangement and functional role of the blood vessels within the human umbilical cord?

   • A) Two umbilical veins transport oxygen-rich blood from the fetus to the placenta, while a single umbilical artery returns deoxygenated blood.
   • B) A single umbilical artery transports oxygenated blood from maternal circulation directly into the fetal inferior vena cava.
   • C) Two umbilical veins carry metabolic wastes away from the fetus, while two umbilical arteries deliver nutrients from the placenta.
   • D) A single umbilical vein carries oxygen- and nutrient-rich blood from the placenta to the fetus, while two umbilical arteries carry deoxygenated blood and wastes from the fetus to the placenta.
4. 4.

   During early human pregnancy, which hormone is secreted by the blastocyst to prevent the degeneration of the corpus luteum and ensure continued progesterone production?

   • A) Prolactin
   • B) Luteinizing hormone
   • C) Human chorionic gonadotropin
   • D) Gonadotropin-releasing hormone
5. 5.

   Which hormone is primarily responsible for stimulating powerful contractions of the uterine smooth muscle during human labor through a positive feedback loop?

   • A) Progesterone
   • B) Human chorionic gonadotropin
   • C) Prolactin
   • D) Oxytocin

Answers and step-by-step solutions appear after you finish the test.