Touch, Smell, and Taste
Although it is a chilly, snowy morning, the blankets are warm and inviting. Your bedroom fills with the aroma of sizzling, crisp bacon. Is it better to be warm and comfy in bed? Perhaps you should go get some sizzling bacon, buttered toast, and hot cocoa for breakfast. Your senses of touch, taste, and smell will impact your selection.
Touch
Contact, pressure, cold, warmth, and pain are the five distinct feelings that make up your sense of touch. Tactile corpuscles are the sensors for touch. Tactile corpuscles are nerve endings that respond to external stimuli by changing form and transmitting signals to the brain or spinal cord. Figure 3-15 depicts the many forms of tac tile corpuscles.
Pain receptors can also be found in the outer layers of several internal organs, in addition to those found in the skin. The presence of pain near an internal organ indicates that it is not functioning properly. This information is critical in assisting doctors in identifying life-threatening illnesses and injuries.
Touch sensations are more sensitive in certain regions of the body than in others.
This is due to the fact that the tactile corpuscles are not equally distributed throughout the body. They are grouped together. The most sensitive areas of your body are the hairless portions, such as your fingers, lips, and tongue. The back of the shoulders is the least sensitive region. However, you have around 100 pressure receptors and 60 pain receptors in a region on your fingertip the size of a period.
The lack of any touch feeling for an extended period of time might indicate a significant health condition. Loss of sensation in the limbs, for example, might be a symptom of poor blood circulation, which could be caused by a condition like diabetes. If you lose any of these feelings, talk to your doctor.
Taste
In front of a mirror, examine your tongue. You'll see that it's not smooth, but rather a jumble of small lumps. Taste buds can be found within these bumps. Taste buds are small organs that contain food-receiving receptors. On your tongue and in the back of your mouth, you have roughly 9000 taste buds.
Taste receptors in the taste buds must be activated by food particles transported in saliva in order to taste. Food particles dissolved in saliva enter each taste bud through a small hole at the top. The nerve at the base of the taste bud is stimulated by the meal. The nerve sends a signal to the brain, which recognises the flavour.
In general, four characteristics in food elicit a response from taste receptors. They can distinguish between bitter, sweet, salty, and sour flavours. Taste buds are not all receptive to the same flavours in food. The placement of the taste centres on the tongue is depicted in Figure 3-16. Taste buds that are sensitive to bitter foods, for example, are found towards the rear of the tongue. This is why some meals leave a bitter taste in your mouth after you eat them.
The bitterness is not noticeable until you consume them. Many foods have an impact on several taste centres. Lemon drops, for example, are sweet and sour at the same time.
Smell
The sense of smell, like the senses of touch and taste, is based on the activation of receptors. Smell-sensitive receptors are known as olfactory nerve reactors. As illustrated in Figure 3-17, they are situated in a tiny part of the nasal cavity. There are up to 50 distinct types of scent receptors in your body.
These receptors, according to scientists, are triggered by chemicals in the air. As you breathe, these chemicals trigger receptors. The olfactory bulb receives impulses from the olfactory nerve receptors. The olfactory bulb sends messages to the brain, which recognises the scent.
Review of the Lesson
The sensations of touch, taste, and smell provide you with a tremendous deal of pleasure while also assisting you in avoiding danger. All of these senses rely on receptors to transmit information to the brain. The brain decodes the signals and directs the body's response. Despite their similarities, the sensations of smell and taste are two distinct senses.