A receptor is a specialized molecule or sensory structure that detects a specific signal, stimulus, or change and initiates or contributes to a biological response.
Some receptors are located on the surface of cells, while others are found inside cells.
At the cellular level, receptors are often proteins that recognize specific molecules such as hormones or neurotransmitters. Sensory receptors can detect physical or chemical stimuli such as touch, temperature, light, or sound.
A receptor does not necessarily produce the final response itself; it detects the signal and initiates or modifies downstream processes.
QUICK FACT
A hormone can affect only cells that have the appropriate receptors for it.
COMMONLY CONFUSED WITH
- Hormone: a chemical messenger that can bind to a receptor.
- Neurotransmitter: a chemical messenger released by nerve cells that can act on receptors.
SEE ALSO
