Final answer:
The olfactory epithelium is located in the roof of the nasal cavity and contains neurons essential for the sense of smell.
Step-by-step explanation:
The olfactory epithelium is located in the roof of the nasal cavity. This specialized tissue contains bipolar sensory neurons, also known as olfactory receptor neurons, which are essential for our sense of smell. Airborne odorant molecules enter the nose and dissolve in the mucus of the olfactory epithelium. They bind to receptors on the dendrites of these neurons, leading to the generation of nerve signals that are transmitted to the brain via the olfactory bulb. Humans have various olfactory receptors that can detect a wide range of odors.