Jacobson's Organ is the vomeronasal scenting organ located in the...

• A. In the nasal cavity behind the nostrils
• B. In the inner ear
• C. In roof of mouth
• D. On the tongue tip

Answer: (C)

The vomeronasal (Jacobson’s) organ is a pheromone-detecting structure, and in dogs it is located in the roof of the mouth. Its ducts open into the oral cavity behind the upper teeth, so pheromones sampled from the environment can be drawn into the organ when a dog uses a flehmen-like gesture or breathes with the mouth partly closed. This placement helps explain why dogs often sniff and then curl their lips or hold their mouth open slightly during scent investigation. The other options point to locations associated with different systems (the main sense of smell is in the nasal cavity behind the nostrils; the inner ear is unrelated; the tongue tip is not involved in pheromone detection).