Editing Gastropoda (section)

=== Sensory organs and nervous system ===
[[File:Vinogradski puz glava.jpg|thumb|The upper pair of [[tentacle]]s on the head of ''Helix pomatia'' have eye spots, but the main sensory organs of the snail are sensory receptors for [[olfaction]], situated in the [[epithelium]] of the tentacles.]]
{{main|Sensory organs of gastropods|Nervous system of gastropods}}

The [[sense|sensory organs]] of gastropods include [[olfaction|olfactory organs]], eyes, [[statocyst]]s and [[mechanoreceptor]]s.<ref name="sensory"/> Gastropods have no hearing.<ref name="sensory">Chase R.: ''Sensory Organs and the Nervous System''. in Barker G. M. (ed.): ''The biology of terrestrial molluscs''. CABI Publishing, Oxon, UK, 2001, {{ISBN|0-85199-318-4}}. 1-146, cited pages: 179–211.</ref>

In terrestrial gastropods (land snails and slugs), the olfactory organs, located on the tips of the four [[tentacle]]s, are the most important sensory organ.<ref name="sensory"/> The chemosensory organs of [[opisthobranch]] marine gastropods are called [[rhinophore]]s.

The majority of gastropods have simple visual organs, eye spots either at the tip or [[Leptopoma|base]] of the tentacles. However, "eyes" in gastropods range from simple [[ocelli]] that only distinguish light and dark, to more complex [[Eye#Pit eyes|pit eyes]], and even to [[Eye#Spherical lens eye|lens eyes]].<ref>{{cite book | last=Götting | first=Klaus-Jürgen | title= Lexikon der Biologie | chapter=Schnecken | editor=Becker, U. |editor2=Ganter, S. |editor3=Just, C. |editor4=Sauermost, R. | year=1994 | publisher=Spektrum Akademischer Verlag | location=Heidelberg | isbn=978-3-86025-156-0}}</ref> In land snails and slugs, vision is not the most important sense, because they are mainly [[Nocturnality|nocturnal]] animals.<ref name="sensory"/>

The nervous system of gastropods includes the [[peripheral nervous system]] and the [[central nervous system]]. The central nervous system consists of [[ganglia]] connected by nerve cells. It includes paired ganglia: the cerebral ganglia, pedal ganglia, [[Osphradium|osphradial]] ganglia, pleural ganglia, parietal ganglia and the visceral ganglia. There are sometimes also buccal ganglia.<ref name="sensory"/>