Chapter 16 - Section 16.1 - Properties and Types of Sensory Receptors - Apply What You Know - Page 581: 1

Cold and warm receptors in the skin and elsewhere in the body can be classified as phasic receptors, with some degree of tonic response as well. Let's break down why they exhibit both phasic and tonic characteristics: 1. **Phasic Response:** - Phasic receptors are sensitive to changes in stimulus intensity or variations in the stimulus. They respond vigorously when a change in temperature occurs but may become less responsive if the temperature remains constant. - For example, when you first immerse yourself in a hot bath, warm receptors in your skin will respond vigorously to the sudden increase in temperature. Similarly, when you enter a cold lake, cold receptors will respond to the initial drop in temperature. - These initial responses signal the change in temperature, and they help you quickly detect and respond to temperature fluctuations in your environment. Phasic responses are important for alerting the body to potential threats or changes in the external environment. 2. **Tonic Response:** - Tonic receptors, on the other hand, are characterized by a continuous, sustained response to a constant stimulus. They do not adapt quickly to changes in stimulus intensity. - While cold and warm receptors exhibit phasic responses to temperature changes, they also have a degree of tonic activity. Even after the initial response to a change in temperature, they continue to provide information about the ongoing temperature of the skin or body. - This tonic response helps maintain awareness of the ambient temperature and contributes to the sensation of comfort or discomfort in response to prolonged exposure to hot or cold conditions. - For example, if you stay in a hot bath for an extended period, warm receptors continue to signal the skin's warmth, which can become uncomfortable over time. Conversely, cold receptors provide continuous feedback about the skin's exposure to cold, helping you gauge the level of discomfort in a cold environment. In summary, cold and warm receptors exhibit both phasic and tonic characteristics. Their phasic responses allow for rapid detection of temperature changes, while their tonic responses provide ongoing information about the current temperature, contributing to the sensation of comfort or discomfort in different thermal environments.

Cold and warm receptors in the skin and elsewhere in the body can be classified as phasic receptors, with some degree of tonic response as well. Let's break down why they exhibit both phasic and tonic characteristics: 1. **Phasic Response:** - Phasic receptors are sensitive to changes in stimulus intensity or variations in the stimulus. They respond vigorously when a change in temperature occurs but may become less responsive if the temperature remains constant. - For example, when you first immerse yourself in a hot bath, warm receptors in your skin will respond vigorously to the sudden increase in temperature. Similarly, when you enter a cold lake, cold receptors will respond to the initial drop in temperature. - These initial responses signal the change in temperature, and they help you quickly detect and respond to temperature fluctuations in your environment. Phasic responses are important for alerting the body to potential threats or changes in the external environment. 2. **Tonic Response:** - Tonic receptors, on the other hand, are characterized by a continuous, sustained response to a constant stimulus. They do not adapt quickly to changes in stimulus intensity. - While cold and warm receptors exhibit phasic responses to temperature changes, they also have a degree of tonic activity. Even after the initial response to a change in temperature, they continue to provide information about the ongoing temperature of the skin or body. - This tonic response helps maintain awareness of the ambient temperature and contributes to the sensation of comfort or discomfort in response to prolonged exposure to hot or cold conditions. - For example, if you stay in a hot bath for an extended period, warm receptors continue to signal the skin's warmth, which can become uncomfortable over time. Conversely, cold receptors provide continuous feedback about the skin's exposure to cold, helping you gauge the level of discomfort in a cold environment. In summary, cold and warm receptors exhibit both phasic and tonic characteristics. Their phasic responses allow for rapid detection of temperature changes, while their tonic responses provide ongoing information about the current temperature, contributing to the sensation of comfort or discomfort in different thermal environments.