receptor
/rɪˈsɛptə
/noun Physiology
1An organ or cell able to respond to light, heat, or other external stimulus and transmit a signal to a sensory nerve: the retina of the octopus has up to 20 million light receptors...
- In the special sense organs, such as the eye and the ear, highly specialized receptors respond to light and sound.
- Our own skin contains a battery of touch receptors that produce nerve signals when pressed.
- However, they have some ability to sense light through receptors in the epidermis.
1.1A region of tissue, or a molecule in a cell membrane, which responds specifically to a particular neurotransmitter, hormone, antigen, or other substance: when viruses succeed in binding to cell membrane receptors they still have to enter the cell before they can replicate...
- When the neurotransmitter binds with the receptor, the next cell responds accordingly.
- Hormones work by docking with a specific receptor on a cell, which then responds by turning on genes.
- Finally, the presence of a specific receptor in the target tissue is required for a hormone to have its effect.
Origin
Early 20th century: coined in German from Latin receptor, from recept- 'taken back', from the verb recipere (see receive).