Which cells within the olfactory epithelium are responsible for responding to odors?

The cells responsible for responding to odors within the olfactory epithelium are the olfactory receptors. These receptor cells have specialized structures that are sensitive to various odorant molecules. When these molecules bind to the receptors, they initiate a signal transduction pathway that ultimately sends signals to the brain, enabling the perception of smell.

Olfactory receptors are unique because they are specialized neurons, which allows them to play a direct role in the detection of odorants. They have long, hair-like projections called cilia, which increase the surface area for detecting odorants in the nasal cavity. This makes them critically important in the initial stages of the olfactory process.

The other types of cells in the olfactory epithelium, such as supporting cells, basal cells, and glial cells, serve different functions. Supporting cells provide structural and metabolic support without directly participating in odor detection. Basal cells serve as progenitors that can differentiate into new olfactory receptor neurons but do not themselves respond to odors. Glial cells support neuronal functions but are not involved in the olfactory process. Thus, the olfactory receptors are indeed the key players in the sense of smell.