Like mammals, flies have two systems helping them sense the world, olfactory and gustatory systems. They use olfactory system to sense volatile chemicals whereas gustatory system to feel soluble compound.
Their olfactory system consists of two third antenna segments on the head and the maxillary palp. Those two appendages are covered by hundreds of sensillia each of which is filled with dendrites of two to four neurons. Those neurons are sensitive to volatile chemicals so they are called olfactory sensory neurons (OSN). Those neurons project to antenna lobes in the brains and signals get organized and coordinated in the brain.
The gustatory system is comprised of proboscis and the sensillia all over the body including wings and legs. Sensory neurons project to the subesophageal ganglion which is a higher level of gustatory signal center. The advantage of having gustatory sensory neurons on legs and wings is that flies do not have to be at the risk of taking some toxic ingestion if they are not sure whether some food is good or not. They can simply use their legs to touch the food then they know it is delicious or shit. On the contrary, we can not tell it until we put something in our mouth, which is risky.....
No comments:
Post a Comment