Barber Practice State Board Practice Exam

Which nerve is responsible for the sense of smell?

1. Optic nerve

2. Olfactory nerve

3. Auditory nerve

4. Trigeminal nerve

The correct answer is: Olfactory nerve

The olfactory nerve is the correct choice as it is specifically responsible for the sense of smell. This cranial nerve is unique because it directly connects the nasal cavity, where olfactory receptors are located, to the olfactory bulb in the brain. When odor molecules bind to these receptors, they trigger electrical signals that travel through the olfactory nerve to be processed by the brain, allowing us to perceive different scents. In contrast, the optic nerve is involved in vision, transmitting visual information from the retina to the brain. The auditory nerve is responsible for hearing, as it carries sound signals from the inner ear to the brain. The trigeminal nerve primarily provides sensations to the face and controls certain muscles used in chewing, but it does not have a role in the sense of smell. Understanding the specific functions of these nerves highlights why the olfactory nerve is the correct answer regarding smell perception.