Suppose you have three water baths in front of you. The temperature of the one on the left is 22°C (cold), the one in the middle is 25°C (room temperature,) and the one on the right is 44°C (warm). At the same time, you place the index finger of your right hand into the warm water bath and the index finger of your left hand into the cold water bath, and you leave them there for 2 minutes. After 2 minutes, why would you no longer feel a difference in temperature between the two water baths?

In the given case, after two minutes the person is not able to make a distinction between the temperature of the two water baths because in the index fingers the sensory receptors are present, which becomes less sensitive due to continuous stimulation over time.  

The dendrites of sensory neurons that perform a unique function of attaining particular types of stimuli are termed as sensory receptors. The sensory receptors are mainly categorized as thermoreceptors, chemoreceptors, photoreceptors, or mechanoreceptors. Mainly the classification of sensory receptors is done by the kind of response produced by the stimulus in the receptor. Generally, sensory receptors react primarily towards any of the four kinds of stimuli, which are temperature, chemicals, light, and pressure.  

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