Final answer:
Taste buds are epithelial cells on the tongue's papillae that respond to chemicals dissolved in saliva, activating gustatory receptor cells which connect to sensory neurons leading to the brain.
Step-by-step explanation:
The epithelial cells that respond to chemicals dissolved in saliva are taste buds. These structures are located on the tongue's surface, housed within small bumps known as papillae. Each taste bud features specialized gustatory receptor cells that detect chemical stimuli when dissolved in saliva. When these chemicals come into contact with the gustatory receptor cells, they trigger a response that activates sensory neurons. These neurons belong to the facial and glossopharyngeal nerves, which then convey the sensation of taste to the brain.
The gustatory system is distinct from olfaction, which pertains to the sense of smell. Olfactory receptors are located in the superior nasal cavity and respond to chemicals in the air, not saliva. This explains why, when we have a stuffy nose, our sense of taste may seem diminished, as both the gustatory and olfactory systems contribute to the flavor perception of food and drinks.