## **Core Concept**
The sensation of warmth is detected by specific thermoreceptors in the skin. Thermoreception is mediated by two main types of receptors: those sensitive to cold and those sensitive to warmth. The warmth sensation is primarily detected by **Ruffini's end-organs**, which are slowly adapting type II mechanoreceptors that also respond to sustained pressure and heat.

## **Why the Correct Answer is Right**
The correct answer, , corresponds to Ruffini's end-organs. These receptors are responsible for detecting warmth and sustained pressure. They are slowly adapting, meaning they continue to fire as long as the stimulus (in this case, warmth) is present. Ruffini's end-organs play a crucial role in sensing the warmth and are found in the dermal layer of the skin.

## **Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not correspond to the receptor responsible for sensing warmth.
* **Option B:** This option might relate to other types of receptors or functions but is not associated with warmth sensation.
* **Option D:** This option is incorrect because it does not accurately represent the receptor or mechanism for detecting warmth.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that thermoreceptors, including those for warmth, are essential for maintaining homeostasis and are distributed throughout the skin. Damage to these receptors or their pathways can result in impaired thermal sensation, which can have significant clinical implications.

## **Correct Answer:** . Ruffini's end-organs