Which nerve is responsible for the sense of smell?

Which nerve is responsible for the sense of smell?

• A. Optic nerve
• B. Oculomotor nerve
• C. Trochlear nerve
• D. Olfactory nerve

Answer: (D)

Smell is carried by the olfactory nerve, the first cranial nerve. It consists of sensory neurons in the nasal mucosa that detect odor molecules. Their fibers pass through the cribriform plate to reach the olfactory bulb, and signals then travel to brain regions that perceive and identify odors. This nerve is dedicated to olfaction, making it the one responsible for sense of smell. The other nerves listed handle vision and eye movement—optic for vision, while oculomotor and trochlear control most eye movements and pupil function—so they are not involved in smelling.

Smell is carried by the olfactory nerve, the first cranial nerve. It consists of sensory neurons in the nasal mucosa that detect odor molecules. Their fibers pass through the cribriform plate to reach the olfactory bulb, and signals then travel to brain regions that perceive and identify odors. This nerve is dedicated to olfaction, making it the one responsible for sense of smell. The other nerves listed handle vision and eye movement—optic for vision, while oculomotor and trochlear control most eye movements and pupil function—so they are not involved in smelling.