Sense of Smell
An animal’s sense of smell is an important part of their facilities because they use it for more than just finding food and rats are no different. Their noses account for average smell as well as other chemicals that represent changes in the atmosphere and emotions of other rats.
As they breathe through their nose, average smells run over a special patch of skin that is covered in smell receptors and olfactory neurons. These receptors are tipped with cilia to which smell particles (odorants) bind and elicit a neural response.
They also have a secondary organ that allows them to pick up, primarily, pheromones of other rats. These pheromones are present in droppings, urine, and secretions from various glands of rats. This organ is called the vomeronasal organ (VNO) This organ is set in the nasal passage alongside the septum.
When they smell and taste, scent molecules in the nose dissolve and make their way to this organ. These odors allow them to recognize issues in their environment and identify the mood and estrus of other rats of their species. Their sense of smell gives them important insight into their surroundings and what is going on in those surroundings.