OB Chapter 35 questions and answers with solutions.

OB Chapter 35 questions and answers
with solutions
In the four-chamber view at 18 weeks of gestation, the ventricles should each measure
approximately _______ millimeters (mm).



a. 2

b. 4

c. 6

d. 8 - ANSWER c. 6



Which one of the following abnormalities is communication between the right and left atrium
that persists after birth?



a. Patent ductus arteriosus

b. Ventricular septal defect

c. Persistent ductus venosus

d. Atrial septal defect - ANSWER d. Atrial septal defect



Which one of the following structures forms in the wall of the sinus venosus near its opening
into the right atrium?



a. Sinoatrial node

b. Atrioventricular node

c. Purkinje fiber node

d. Moderator band - ANSWER a. Sinoatrial node

, The ______________ is the first part of the atrial septum to grow from the dorsal wall of the
primitive atrium. It fuses with the endocardial cushions.



a. septum primum

b. fossa ovale

c. septum secundum

d. fossa ovalis - ANSWER a. septum primum



The embryonic vascular system begins during the _____ week.



a. second

b. third

c. fourth

d. fifth - ANSWER b. third



The cardinal vein returns blood from which one of the following?



a. Embryo

b. Yolk sac

c. Placenta

d. Heart - ANSWER a. Embryo



The primitive cardiovascular system is formed by blood vessels including all of the following
structures except the:



a. yolk sac.