Chemical Senses - Taste and Smell

Chemical Senses - Taste and Smell

Taste and smell are two important chemical senses that allow us to enjoy and detect food and aromas around us. The sensation of taste arises as a result of irritation of the chemoreceptor cells of the tongue, and the sense of smell arises as a result of irritation of the chemoreceptor cells of the nose with specific substances. Let's take a closer look at how these senses work.

Taste buds, also known as taste buds, are found in the mucous membranes of the human tongue and soft palate. Each taste bud consists of several sensory cells connected to sensory neurons and surrounded by supporting cells. They open in pores on the surface of the tongue and are unevenly distributed. Some areas of the tongue are more sensitive to sweet tastes, while others are more sensitive to bitter, sour or salty tastes. There are only four basic taste sensations: sour, salty, bitter and sweet.

Interestingly, the taste of a particular substance depends not only on the sense of taste, but also on the sense of smell. Substances entering the oral cavity pass through the choanae into the nasal cavity and irritate the olfactory organs. Therefore, when you have a runny nose, food may seem relatively tasteless because your sense of smell has been partially or completely lost.

People's ability to taste and smell different substances may vary. For example, some people find the chemical compound phenylthiourea bitter, while others find it tasteless. This ability to taste phenylthiourea is inherited and is caused by a single pair of genes. Thus, hereditary differences may influence the sense of taste in different people.

The olfactory organs are located in the epithelium of the upper part of the nasal cavity and contain olfactory cells. These cells are distinguished from ordinary epithelial cells by the presence of hairs protruding into the mucus layer. When particles of a substance enter the nasal cavity, they reach the olfactory cells and irritate them. Each substance has its own characteristic odor, and the olfactory organs react to very small amounts of the substance.

However, the sensitivity of the olfactory organs quickly becomes dull. Air, which may initially be a strong irritant to the olfactory cells, becomes less noticeable over time. This is called olfactory adaptation. For example, when we are in a room with a specific smell, at first we notice it, but over time our sense of smell gets used to this smell, and we stop feeling it.

Taste and smell are closely related and interact with each other. When we eat, the taste buds on the tongue recognize different tastes, and substances released by food also enter the nasal cavity and irritate the olfactory cells. This explains why, for example, when we have a cold or a stuffy nose, food may seem less tasty to us.

Chemical senses such as taste and smell play an important role in our ability to appreciate, enjoy and select food. They help us identify the foods we prefer and alert us to potentially dangerous or spoiled foods.

Taste and smell also have social and emotional significance. Smells can evoke memories and emotions, and certain scents can be associated with certain events or people. For example, the smell of fresh baked goods can make us feel cozy and comfortable, while the smell of flowers can be associated with pleasant memories.

In general, taste and smell are important aspects of our perception of the world around us, especially in relation to food and aromas. They help us enjoy food and determine the quality and safety of food.