In biology, a tubule is a general term referring to small tube or similar type of structure. Specifically, tubule can refer to:
- a small tube or fistular structure
- a minute tube lined with glandular epithelium
- any hollow cylindrical body structure
- a minute canal found in various structures or organs of the body
- a slender elongated anatomical channel
- a minute tube, especially as an anatomical structure.
Examples of tubules
- Collecting tubules: terminal channels of the nephrons
- Cuvierian tubules: clusters of sticky tubules located at the base of the respiratory tree, which may be discharged by some sea cucumbers (holothurians) when mechanically stimulated (i.e. being threatened by a predator)
- Dentinal tubules or dental canaliculi: minute channels in the dentine of a tooth that extend from the pulp cavity to the cementum or the enamel
- Mesonephric tubule: tubules comprising the mesonephros or temporary kidney of amniotes
- Metanephric tubule: tubules comprising the permanent kidney of amniotes