Author Question: The various systems and organs develop at different states. Which of the following statements is ... (Read 27 times)

sjones · **on:** Jun 27, 2018

The various systems and organs develop at different states. Which of the following statements is accurate?

1. The cardiovascular system is the first organ system to function in the developing human.
2. Hematopoiesis originating in the yolk sac begins in the liver at 10 weeks.
3. The body changes from straight to C shaped at 8 weeks.
4. The gastrointestinal system is mature at 32 weeks.

Question 2

Concerning the development of the respiratory system, maternity nurses should be aware that:

1. the respiratory system doesn't begin development until after the embryonic stage.
2. the infant's lungs are considered mature when the L/S ratio is 1:1, at about 32 weeks.
3. maternal hypertension can decrease maternal placental blood flow, which accele-rates lung maturity.
4. fetal respiratory movements are not visible on ultrasound until at least 16 weeks.

at · **Reply #1 on:** Jun 27, 2018

Answer to Question 1

1
1. Correct. The heart is developmentally complete by the end of the embryonic stage.
2. Incorrect. Hematopoiesis begins in the liver during the sixth week.
3. Incorrect. The body becomes C shaped at 21 weeks
4. Incorrect. The gastrointestinal system is complete at 36 weeks.

Answer to Question 2

3
1. Incorrect. The respiratory system begins development during the embryonic phase and continues into childhood.
2. Incorrect. The infant's lungs are mature when the L/S ratio is 2:1, at about 35 weeks.
3. Correct. The decreased placental blood flow stresses the fetus, increases blood levels of corticosteroids, and so accelerates lung maturity.
4. Incorrect. Lung movements have been seen on ultrasound at 11 weeks.