notochord
Sign in to savethumb|400px|Position of notochordes and axochords in bilaterians. (A) Zebrafish notochord. (B) Ascidian notochord. (C) Lancelet notochord. Notochord is positioned just ventral to the neural tube and dorsal to the gut, flanked by myotome. (D) Notochord homolog in annelid. Cross-section showing the position of the proposed axochord to the ventral mesentery, blood vessel, and nerve chord. Axochord is found to be dorsal to the nerve chord and ventral to gut of the animal. Red: notochord; Magenta: axochord; Green: nerve chord; Blue: epidermis; Yellow: mesoderm.
Key facts
- Embryology.Name
- Notochord
- Embryology.Latin
- notochorda
- Embryology.Image
- Gray19 with color.png
- Embryology.Caption
- Transverse section of a chick embryo of forty-five hours' incubation.
- Embryology.Precursor
- Axial mesoderm
- Embryology.GivesRiseTo
- Nucleus pulposus
via Wikipedia infobox
Research
4,923 papers- Ascidian notochord elongation.Developmental biology · 2019
- Timely TGFβ signalling inhibition induces notochord.Nature · 2025
- The notochord.Current biology : CB · 2004
- The notochord: structure and functions.Cellular and molecular life sciences : CMLS · 2015
- Cellular Processes of Notochord Formation.Advances in experimental medicine and biology · 2018
via PubMed
Article
11 sectionsContents
- Presence
- Structure
- Role in signaling and development
- In amphibians and fish <span class="anchor" id="Flexion stage"></span>
- In humans
- Neurology
- Evolution in chordates
- Post-embryonic retention
- Within lancelets
- Additional images
- References
thumb|400px|Position of notochordes and axochords in bilaterians. (A) Zebrafish notochord. (B) Ascidian notochord. (C) Lancelet notochord. Notochord is positioned just ventral to the neural tube and dorsal to the gut, flanked by myotome. (D) Notochord homolog in annelid. Cross-section showing the position of the proposed axochord to the ventral mesentery, blood vessel, and nerve chord. Axochord is found to be dorsal to the nerve chord and ventral to gut of the animal. Red: notochord; Magenta: axochord; Green: nerve chord; Blue: epidermis; Yellow: mesoderm.
The notochord is an elastic, rod-like structure found in chordates. In vertebrates the notochord is an embryonic structure that disintegrates, as the vertebrae develop, to become the nucleus pulposus in the intervertebral discs of the vertebral column. In non-vertebrate chordates, the notochord persists during development.