Final answer:
Nociceptors detect harmful stimuli and are associated with the perception of pain and sometimes itch, but not skin stretch. Skin stretch is detected by mechanoreceptors such as Ruffini endings.
Step-by-step explanation:
Nociceptors are specialized sensory receptors that are responsible for detecting harmful or potentially harmful stimuli, which are generally perceived as pain. They can be found throughout the body including in internal organs and on the surface of the skin.
The primary role of nociceptors is to respond to a variety of stimuli that are of a sufficient intensity to cause or potentially cause tissue damage. This can include mechanical, chemical, and thermal stimuli. When activated by such stimuli, nociceptors transduce the information into nerve signals that are interpreted as pain by the brain.
Given this information, the correct answer to which nociceptors are responsible for the perception of is D. pain and itch. Itch sensation has been associated with a subset of nociceptors that are also involved in pain transduction, and the stimulation of these particular nociceptors can lead to the perception of itch in addition to pain. Therefore, nociceptors can respond not just to painful stimuli, but specific ones can also be involved in itchy sensations. On the other hand, skin stretch is primarily sensed by mechanoreceptors such as Ruffini endings, not nociceptors.