Final answer:
The discussion covers the biology of taste and smell, describing how taste receptor cells in the tongue and odor receptors in the nasal passages work and their connection to the brain through cranial nerves. Taste and olfaction contribute jointly to the perception of flavors, and impairment in the ability to smell can dramatically affect taste experiences.
Step-by-step explanation:
The subject of this question is focused on the biological systems responsible for taste and smell, which are crucial sensory systems in humans. Taste buds on the tongue contain taste receptor cells, which are activated by molecules from the food we ingest. Supporting and basal cells in these buds are essential for the maintenance and development of taste receptor cells. Moreover, the sense of olfaction, or smell, which involves odor receptors in the nasal passages, is intimately linked to the sense of taste. Odor molecules bind to receptors in the olfactory epithelium, initiating a signal that travels to the brain via the olfactory bulb. The integration of these two senses greatly enriches the perception of flavors.
These taste and odor receptors are linked to the nervous system through cranial nerves, specifically the facial, glossopharyngeal, and vagus nerves. For example, the facial nerve connects to taste buds in the anterior third of the tongue, while the glossopharyngeal nerve connects to those in the posterior two thirds. The sense of taste is not only about the detection of sweet, salty, sour, or bitter substances but also about the overall experience of flavor, which is enhanced by the sense of smell. This is evident when having a stuffy nose impacts one's ability to taste food.