Sensory receptor

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In a sensory system, a sensory receptor is a sensory nerve ending that responds to a stimulus in the internal or external environment of an organism. In response to stimuli, the sensory receptor initiates sensory transduction by creating graded potentials or action potentials in the same cell or in an adjacent one.

Structure of human sensory system


The sensory receptors involved in taste and smell contain receptor molecules that bind to specific chemicals. Odor receptors in olfactory receptor neurons, for example, are activated by interacting with molecular structures on the odor molecule. Similarly, taste receptors (gustatory receptors) in taste buds interact with chemicals in food to produce an action potential.


The sensory receptor functions are the first component in a sensory system.




Adequate stimulus[edit]




Sensory receptors can be classified by location:



Rate of adaptation[edit]

  • A tonic receptor is a sensory receptor that adapts slowly to a stimulus[citation needed] and continues to produce action potentials over the duration of the stimulus.[3] In this way it conveys information about the duration of the stimulus. Some tonic receptors are permanently active and indicate a background level. Examples of such tonic receptors are pain receptors, joint capsule, and muscle spindle.[4]
  • A phasic receptor is a sensory receptor that adapts rapidly to a stimulus. The response of the cell diminishes very quickly and then stops.[citation needed] It does not provide information on the duration of the stimulus;[3] instead some of them convey information on rapid changes in stimulus intensity and rate.[4] An example of a phasic receptor is the Pacinian corpuscle.


Main article: Sensory fiber types


See also[edit]

Additional images[edit]


  1. ^ Michael J. Gregory. "Sensory Systems". Clinton Community College. Retrieved 2013-06-06. 
  2. ^
  3. ^ a b,%2017%2018.ppt[dead link]
  4. ^ a b[dead link]

External links[edit]