Sensory Receptors

 SENSORY RECEPTORS

Sensory receptors are sensory nerve endings or specialized cellscapable of responding to stimuli by developing action potentials. Several types of receptors are associated with both the general and the special senses, and each responds to a different type of stimulus:

Mechanoreceptors (mek′ă-n̄o-r̄e-sep′tŏrz) respond tomechanical stimuli, such as the bending or stretching of receptors.

Chemoreceptors (kem′ō-rē-sep′tŏrz) respond to chemicals,such as odor molecules.

Photoreceptors (fō′tō-rē-sep′tŏrz) respond to light. Thermoreceptors (ther′mō-rē-sep′tŏrz) respond totemperature changes.

Nociceptors (nō′si-sep′tŏrs;noceo,to injure) respond tostimuli that result in the sensation of pain.



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