start stage end stage cranial nerve TAO:0000641 ZFA:0000641 zebrafish_anatomy Twelve pairs of cranial nerves exit/enter the cranium through openings in the skull. The nerves contain efferent axons with motor and glandular functions, as well as afferent axons from cranial ganglia with sensory functions. The nerves are numbered in a rostral to caudal sequence, with the exception of the lateral line nerves. cranial nerves nerve unknown adult