Anatomy Exam Cranial Nerves and Foramina 4

Question 1

Which cranial nerve is responsible for the efferent limb of the gag reflex?

Accepted Answer

CN X (Vagus)

Answer

The vagus nerve (CN X) provides the motor (efferent) response of the gag reflex by elevating the palate and constricting the pharynx; CN IX is the afferent limb.

Question 2

Foramen rotundum transmits which nerve?

Accepted Answer

V2 (Maxillary division)

Answer

The maxillary division (V2) of the trigeminal nerve exits the middle cranial fossa through the foramen rotundum to enter the pterygopalatine fossa.

Question 3

Which cranial nerve passes through the cavernous sinus but does NOT travel within the sinus wall (it runs freely within the sinus)?

Accepted Answer

CN VI (Abducens)

Answer

CN VI passes freely within the cavernous sinus, making it most vulnerable to increased intrasinus pressure; CN III, IV, V1, and V2 travel in the lateral wall.

Question 4

The spinal accessory nerve (CN XI) primarily innervates which muscles?

Accepted Answer

Trapezius and sternocleidomastoid

Answer

The accessory nerve (CN XI) provides motor innervation to the trapezius and sternocleidomastoid muscles.

Question 5

Which foramen is the most posterior of the three foramina in the posterior cranial fossa floor?

Accepted Answer

Foramen magnum

Answer

The foramen magnum is the largest and most posterior foramen in the skull base, located in the posterior cranial fossa and transmitting the brainstem, vertebral arteries, and CN XI spinal roots.

Anatomy Exam Practice Test

Anatomy Exam Practice Test

Anatomy Exam Cranial Nerves and Foramina 4