Final answer:
Olfaction and gustation are termed chemical senses due to their reliance on chemoreceptors in the tongue and nose to detect environmental chemicals, which the brain then interprets as flavors. The sense of taste and smell are highly interconnected, working together to provide the perception of flavor.
Step-by-step explanation:
Olfaction (smell) and gustation (taste) are referred to as chemical senses because they detect chemicals in the environment through specialized sensory receptors. These receptors, known as chemoreceptors, are primarily found on the tongue and in the nasal passages. When you experience the flavor of food, you are sensing a combination of both gustatory (taste) and olfactory (smell) stimuli. For example, sweetness often indicates high-caloric content, which can be essential for survival, while bitterness may suggest toxicity.
Chemoreceptors in taste buds on the tongue detect the presence of certain chemicals, allowing us to taste. Similarly, odor receptors in the nose pick up on different chemicals in the air, contributing to the sense of smell. Humans have around 350 types of olfactory receptors, which allow us to detect a wide range of odors. These chemical senses work in tandem to provide the perception of flavor, which can be affected by factors such as nasal congestion, reducing the ability to taste.
Both the sense of taste and smell send nerve impulses to the brain, where they are interpreted, allowing us to recognize and respond to various substances we encounter in our environment.