Final answer:
Cranial nerve I (CNV1) exits the cranium through the cribriform plate, while CNV2 and CNV3 exit through the optic canal and the superior orbital fissure, respectively. The mnemonic "On Old Olympus' Towering Tops/A Finn And German Viewed Some Hops" helps with the order and "Some Say Marry Money But My Brother Says Brains Beauty Matter More" for their functions.
Step-by-step explanation:
The cranial nerves exit the cranium through various foramina and fissures. Cranial nerve I (CNV1), also known as the olfactory nerve, exits the cranium through the cribriform plate of the ethmoid bone. Cranial nerves II (CNV2, the optic nerve) and III (CNV3, the oculomotor nerve) exit the cranium through the optic canal and the superior orbital fissure, respectively. Remembering the mnemonic "On Old Olympus' Towering Tops/A Finn And German Viewed Some Hops" can be useful, as it encodes the order of the cranial nerves. Each cranial nerve has a specific function. For instance, CNV1 is purely sensory, CNV2 is also sensory, and CNV3 is primarily motor. A useful rhyme for remembering the basic functions of the cranial nerves is "Some Say Marry Money But My Brother Says Brains Beauty Matter More". Understanding the functional classification and exit points of cranial nerves is essential for cranial nerve exams and neuroanatomy.