cardiovascular system?

Question 1

phrenic nerve

Answer 1

originates from the cervical spinal roots (C3, C4, C5) and courses anteriorly over the lung root. It continues downward between the pericardium and the pleura, primarily heading toward the diaphragm, which it innervates.
remains anterior so it can safely reach the diaphragm without interference

Question 2

vagus nerve

Answer 2

descends from the brainstem and passes posterior to the lung root, then gives rise to branches forming the pulmonary plexus and contributing to parasympathetic regulation of lung function.
posterior route as it distributes autonomic fibers to thoracic organs.