Chemoreceptor

Definition

A specialized sensory cell or neuronal structure that detects chemical stimuli and transduces them into biological signals, typically action potentials or neurotransmitter release. In arthropods, chemoreceptors mediate critical behaviors including foraging, mate location, predator avoidance, and host recognition.

Etymology

From Greek khēmeia (alchemy/chemistry) + Latin receptor (receiver)

Example

The antennae of male silkmoths (Bombyx mori) bear highly sensitive chemoreceptors that detect the sex pheromone bombykol at concentrations below one molecule per receptor, enabling location of females from several kilometers downwind.

Synonyms

• chemosensor

Related Terms

• olfactory receptor
• gustatory receptor
• mechanoreceptor
• Sensillum
• antenna
• maxillary palp
• Pheromone
• tropotaxis
• klinotaxis

Usage Notes

Distinguished from mechanoreceptors (detecting physical deformation) and photoreceptors (detecting light). In insect literature, 'chemoreceptor' often refers specifically to gustatory (contact) and olfactory (volatile) receptors, though these are molecularly and anatomically distinct. Gustatory chemoreceptors typically occur on mouthparts, tarsi, and ovipositors; olfactory chemoreceptors dominate antennae and palps. The term is broader than 'olfactory receptor' (restricted to smell) or 'taste receptor' (restricted to contact chemoreception). Some sources reserve 'chemoreceptor' for internal sensors detecting blood gases (as in vertebrate carotid bodies), but arthropod biologists apply it broadly to external chemical sensors.