What are the different types of nociceptors?

• A. Mechanical, Chemical, Plymodal
• B. Thermal, Chemical, Mechanical
• C. Mechanical only
• D. Proprioceptive, Mechanical, Chemical

Answer: (A)

Nociceptors are sensory endings that signal potential tissue damage, and they’re grouped by the kind of stimulus that excites them. The classic modalities are mechanical nociceptors (triggered by strong pressure or stretch), thermal nociceptors (respond to extreme heat or cold), and chemical nociceptors (activated by irritants, acidic pH, and related chemicals). Some fibers are polymodal, meaning they can be activated by more than one type of noxious stimulus, but most basic discussions treat mechanical, thermal, and chemical as the core categories. The option that includes mechanical, chemical, and thermal aligns with this standard triad, making it the most complete and widely accepted representation. The other choices either leave out a major modality, include a non-nociceptive sense like proprioception, or reduce the set to just mechanical.