Which of the following is a remnant of a short, muscular blood vessel that existed in the fetus?
A)are located within the fold of dura mater lying between the cerebral hemispheres.
B)fuse with the radial and ulnar veins.
C)travel a short distance inside the thoracic cavity to meet and merge with the external and internal jugular veins, forming the innominate vein.
D)combine to create the superior vena cava.
E)drain the posterior surface of the skull, descending within the transverse foramina of the cervical vertebrae.
Which of the following is a short-circuit that exists between the pulmonary and aortic trunks in the fetus?
In a fetus, blood from the right atrium can flow freely to the left atrium through the ________, thus bypassing the pulmonary circuit.