Rather than talking in terms of scents, smells, or tastes, another way to understand fish attractants is in terms of the molecules they contain and what response those molecules are supposed to trigger in a bass nose, mouth and therefore the bass brain. So let's start by looking up the nose of a bass. Bass have left and right nostrils just above their mouths. Some studies have also suggested that bass have scent and taste receptors inside and even outside their mouths. Regardless of where they are located, each receptor cell resembles a tiny pit or cavity, each with its own little pathway leading to the brain.
Receptor cells come in all different sizes and types.
Some are triggered only by scents, others in and around the mouth are triggered only by tastes. Some receptor cells are only triggered by molecules of odorless, tasteless chemicals such as sex hormones during mating, or fear or shock pheromones given off by frightened or injured creatures. A spawning male's milt cells even have such receptors on it, and use them to detect and swim towards chemicals emitted into the water by the female's eggs, thereby finding and fertilizing them. In the nose or mouth, the receptor cells only send scent messages to the brain if the correct size and type of water-borne molecule fits correctly into the receptor cell cavity. If a scent molecule is not the right size or type to fit properly into a particular receptor cell cavity, then no message gets fired to the brain.