Question

Name the 1) afferent and 2) efferent for the constriction of pupil to light (PARASYMP) reflex.

A. Afferent: Optic nerve (CN II); Efferent: Oculomotor nerve (CN III)
B. Afferent: Oculomotor nerve (CN III); Efferent: Optic nerve (CN II)
C. Afferent: Facial nerve (CN VII); Efferent: Trigeminal nerve (CN V)
D. Afferent: Trochlear nerve (CN IV); Efferent: Abducens nerve (CN VI)

Answer 1

The correct afferent nerve for the pupil constriction reflex to light is the Optic nerve (CN II), and the efferent nerve is the Oculomotor nerve (CN III), making the answer A: Afferent: Optic nerve (CN II); Efferent: Oculomotor nerve (CN III). The correct answer is A.

Step-by-step explanation:

The student is asking about the neurological control of the pupil constriction reflex in response to light (parasympathetic response). The correct afferent and efferent nerves for the pupillary light reflex are:

1. Afferent: Optic nerve (CN II) - which carries the sensory signal from the retina to the brain.
2. Efferent: Oculomotor nerve (CN III) - which carries the motor signal from the brain to the iris' circular muscles, resulting in pupil constriction.

Hence, the correct answer is A. Afferent: Optic nerve (CN II); Efferent: Oculomotor nerve (CN III).