Question

Which of the following cranial nerves of man is both sensory and motor?
A) Optic
B) Auditory
C) Olfactory
D) Trigeminal

Answer 1

Cranial nerves are the nerves that emerge directly from the brain. There are 12 pairs of cranial nerves present. Cranial nerves relay information between the brain and the parts of the body. They include the special senses of vision, taste, smell and hearing.

Complete answer:
Optic nerves:The optic nerve is the sensory nerve. These nerves connect the eyes to the brain.The optic nerves carry the impulses formed by the retina to the brain.Brain recognizes the image that is dispatched by the optic nerves in the brain.The optic nerve is the second cranial nerve.The word optic comes from the greek word ‘optikos’ which means sight.
Auditory nerves : Auditory nerve is the sensory nerve.There are the eight pairs of the cranial nerves.This nerve connects the inner ear with that of the brain.These nerves transmit the impulses that are concerned with hearing and balance.These nerves are composed of cochlear nerves and vestibular nerves.
Olfactory nerves : Olfactory nerve is also the sensory nerve.Olfactory nerve is the first cranial nerve.It conveys the sensory information that is related to the smell.It is the shortest cranial nerve and passes its receptors in the nasal mucosa to the forebrain.
Trigeminal nerves : Trigeminal nerve is the largest nerve in all the 12 cranial nerves.The main function of the trigeminal nerves is to transmit sensory information to the skin, sinuses and mucous membrane in the face.Trigeminal nerves also stimulate the movement in the jaw muscles.The trigeminal nerve has three different divisions.Each division has a slightly different function.Trigeminal nerve is both motor and sensory nerve.
Therefore, it has been clear from the above discussion that Trigeminal cranial nerves of the man is both sensory and motor.
Hence, option D is the correct answer.
Note: Cranial nerves have a corresponding roman numeral between I and XII. The number is based on the location of nerves from the front to back. For example – olfactory nerve is the closet nerve to the front of the head that’s why it is designated as number I.