part of develops from ends during starts during olfactory placode olfactory nerve Cranial nerve that supplies the nasal organ. It leaves the olfactory lobe, passes through the fenestra olfactoria into the nasal capsule, and there divides into the ramus profundus and ramus dorsalis. UBERON:0001579 cranial nerve I xenopus_anatomy XAO:0000426 cranial nerve death olfactory system NF stage 32