Question

1. nociceptors are classified based on the stimuli and type of information they are relaying and contains two main fibers: a-delta and c-fibers. select all that apply regarding c-fibers.

select all that apply.

• poorly localized, slow pain
• myelinated
• activated by only thermal or mechanical stimuli
• large receptor fields to relay pain intensity
• acute, fast pain
• activated by thermal, mechanical, or chemical stimuli

Explanation:

To solve this, we recall the properties of C - fibers:

1. C - fibers are unmyelinated, conduct slowly, and carry poorly localized, slow - onset pain (like aching pain).
2. They have large receptor fields which help in relaying pain intensity.
3. They can be activated by thermal, mechanical, or chemical stimuli (not just thermal or mechanical).
4. A - delta fibers are responsible for acute, fast pain and are myelinated.

So the correct options are:

• Poorly localized, slow pain: C - fibers carry pain that is hard to localize and is slow - acting.
• Large receptor fields to relay pain intensity: C - fibers have large receptor fields for this purpose.
• Activated by thermal, mechanical, or chemical stimuli: C - fibers respond to multiple types of noxious stimuli.

The incorrect options:

• Myelinated: C - fibers are unmyelinated.
• Activated by only thermal or mechanical stimuli: C - fibers also respond to chemical stimuli.
• Acute, fast pain: This is the domain of A - delta fibers.

Answer:

• Poorly localized, slow pain
• Large receptor fields to relay pain intensity
• Activated by thermal, mechanical, or chemical stimuli