Antenna (biology)

Antenna (biology)

Antennae (singular: antenna) in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes.

In arthropods, antennae are connected to the front-most segments. In crustaceans, they are biramous and present on the first two segments of the head, with the smaller pair known as antennules. All other arthropod groups - except chelicerates and proturans, which have none - have a single, uniramous pair of antennae. These antennae are jointed, at least at the base, and, in general, extend forward from the head. They are sensory organs, although the exact nature of what they sense and how they sense it is not the same in all groups, or always clear. Functions may variously include sensing touch, air motion, heat, vibration (sound), and especially olfaction (smell) or gustation (taste).