Anatomy Exam Cranial Nerves and Foramina 3 — Questions and Answers
Question 1: Which cranial nerve exits through the cribriform plate of the ethmoid bone?
- CN II (Optic)
- CN I (Olfactory) (Correct answer)
- CN V1 (Ophthalmic)
- CN III (Oculomotor)
Correct answer: CN I (Olfactory)
The olfactory nerve (CN I) consists of multiple fila olfactoria that pass through the perforations of the cribriform plate to reach the olfactory bulb.
Question 2: A tumor compressing the jugular foramen would most likely affect which set of cranial nerves?
- CN VII, VIII, IX
- CN IX, X, XI (Correct answer)
- CN X, XI, XII
- CN V, VI, VII
Correct answer: CN IX, X, XI
The jugular foramen transmits CN IX (glossopharyngeal), CN X (vagus), and CN XI (accessory nerve), along with the sigmoid sinus becoming the internal jugular vein.
Question 3: The optic canal transmits which two structures?
- Optic nerve and ophthalmic artery (Correct answer)
- Optic nerve and optic chiasm
- CN III and ophthalmic artery
- Optic nerve and central retinal vein
Correct answer: Optic nerve and ophthalmic artery
The optic canal transmits the optic nerve (CN II) and the ophthalmic artery, which is a branch of the internal carotid artery.
Question 4: Which cranial nerve provides motor innervation to the tongue muscles (except palatoglossus)?
- CN IX (Glossopharyngeal)
- CN X (Vagus)
- CN XII (Hypoglossal) (Correct answer)
- CN VII (Facial)
Correct answer: CN XII (Hypoglossal)
The hypoglossal nerve (CN XII) innervates all intrinsic and most extrinsic tongue muscles; palatoglossus is innervated by CN X.
Question 5: Which foramen is located in the posterior cranial fossa and transmits the hypoglossal nerve?
- Jugular foramen
- Foramen magnum
- Hypoglossal canal (Correct answer)
- Stylomastoid foramen
Correct answer: Hypoglossal canal
The hypoglossal canal (anterior condylar canal) is located in the occipital bone above the occipital condyles and transmits CN XII.
Question 6: The vestibulocochlear nerve (CN VIII) carries which functional modalities?
- GSA and GVA
- SVA and GVA
- SSA only (Correct answer)
- GSA only
Correct answer: SSA only
CN VIII carries only special somatic afferent (SSA) fibers, conveying hearing from the cochlear division and balance from the vestibular division.
Question 7: A patient with a lesion at the internal acoustic meatus would most likely present with deficits in which cranial nerves?
- CN V and VI
- CN VII and VIII (Correct answer)
- CN IX and X
- CN III and IV
Correct answer: CN VII and VIII
The internal acoustic meatus (internal auditory canal) transmits CN VII (facial) and CN VIII (vestibulocochlear), along with the labyrinthine artery.
Anatomy Exam Cranial Nerves and Foramina 3
Which cranial nerve exits through the cribriform plate of the ethmoid bone?