(N/A) Receptors are specialized sensory structures (organs,tissues,or cells) present throughout the body. They are either grouped together,as in the case of the eye or ear,or scattered,as in the case of the skin.
Functions of receptors:
$(i)$ They detect external stimuli such as heat,light,sound,or pain.
$(ii)$ They trigger an electrical impulse in the sensory neurons,which transmits the information to the central nervous system (spinal cord or brain).
Problems when receptors do not work properly:
If receptors are damaged,the body fails to perceive external stimuli. For example,if the heat receptors in the skin are damaged,a person might accidentally touch a hot object and suffer severe burns because the brain does not receive the warning signal of pain or heat. This lack of sensory feedback can lead to serious injuries or accidents.