Fast-adapting receptors are called __________.

• A. sensory receptors
• B. tonic receptors
• C. threshold receptors
• D. phasic receptors

Answer: (D)

Verified step by step guidance

1. Understand the types of sensory receptors: Sensory receptors are specialized cells or nerve endings that respond to changes in the environment. They can be classified based on their adaptation speed to stimuli.
2. Differentiate between tonic and phasic receptors: Tonic receptors adapt slowly to a stimulus and continue to produce action potentials over the duration of the stimulus. Phasic receptors, on the other hand, adapt quickly to a stimulus and stop responding after the initial change.
3. Identify the characteristics of fast-adapting receptors: Fast-adapting receptors are those that respond quickly to changes in stimuli but do not maintain the response for a prolonged period. This is a key feature of phasic receptors.
4. Relate the characteristics to the options provided: Among the options given, phasic receptors are known for their fast adaptation to stimuli, making them the correct choice.
5. Conclude with the correct identification: Based on the understanding of receptor types and their adaptation speeds, fast-adapting receptors are identified as phasic receptors.