a group of specialized receptor cells which, in non-human mammals, is vulnerable to pheromones, and thereby plays an imperative role in the carnal acts and reproductive physiology of these animals. With regard to humans, this system responds physiologically to chemical arousal and thus, arouses brain centers, but its part in human olfaction isn't known. Commonly referred to as Jacobson

VOMERONASAL SYSTEM: "The vomeronasal system is olfactory sense organ found in many animals. "