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Ch. 28 Pregnancy and Human Development
Marieb - Human Anatomy & Physiology 11th Edition
Marieb, Hoehn11th EditionHuman Anatomy & PhysiologyISBN: 9780136874034당신이 사용하는 게 아니라요?교과서 변경
28장, 문제 6

Which of the following changes occur in the baby’s cardiovascular system after birth?
(a) umbilical arteries and vein become fibrosed
(b) pulmonary circulation begins to function, and pressure in the left side of the heart increases
(c) the ductus venosus becomes obliterated, as does the ductus arteriosus
(d) all of these

검증된 단계별 안내
1
Step 1: Understand the fetal circulation system before birth, which includes structures like the umbilical arteries and vein, ductus venosus, and ductus arteriosus that help bypass the lungs and liver since the fetus gets oxygen from the placenta.
Step 2: Recognize that after birth, the baby starts breathing air, so the lungs expand and pulmonary circulation begins to function, increasing blood flow to the lungs and raising pressure on the left side of the heart.
Step 3: Know that the umbilical arteries and vein, which carried blood to and from the placenta, close and become fibrosed (turn into fibrous tissue) since the placenta is no longer needed for oxygen exchange.
Step 4: Understand that the ductus venosus (which shunted blood away from the liver) and the ductus arteriosus (which connected the pulmonary artery to the aorta) both close and become obliterated, redirecting blood flow through the lungs and liver as normal adult circulation begins.
Step 5: Conclude that all these changes occur after birth, so the correct answer is that all the listed changes happen in the baby's cardiovascular system after birth.

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Changes in Umbilical Vessels After Birth

After birth, the umbilical arteries and vein, which previously carried blood between the fetus and placenta, close and become fibrosed. This process stops placental blood flow and transforms these vessels into ligaments, marking a key step in the newborn's independent circulation.
추천 영상:
가이드 코스
5:34
Types of Blood Vessels

Initiation of Pulmonary Circulation

At birth, the lungs expand and pulmonary circulation begins as the baby takes its first breaths. This causes a drop in pulmonary vascular resistance and an increase in blood flow to the lungs, raising pressure in the left side of the heart and enabling oxygenated blood to circulate systemically.
추천 영상:
가이드 코스
05:03
1) Initiation of Translation

Closure of Fetal Shunts: Ductus Venosus and Ductus Arteriosus

The ductus venosus and ductus arteriosus are fetal blood vessels that bypass the liver and lungs, respectively. After birth, these shunts close and become fibrous ligaments, redirecting blood flow through the liver and lungs, which is essential for normal postnatal circulation.
추천 영상:
02:12
Reproduction
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