Membrane organ that surrounds the brain and the spinal cord. [ http://en.wikipedia.org/wiki/Meninx FMA:9589 http://www.shsu.edu/~bio_mlt/Chap15.html ]
Synonyms: meningeal layer layer of meninges
Term information
- FMA:9589
- EMAPA:32660
- VHOG:0001295
- EV:0100312
- MAT:0000113
- GAID:687
- TAO:0001355
- NLXANAT:090204
- Wikipedia:Meninx
- ZFA:0001355
- EFO:0000867
- CALOHA:TS-1177
- MA:0001113
- BTO:0000144
- MESH:D008578
- UMLS:C0025285 (ncithesaurus:Meninges)
- NCIT:C12348
uberon_slim, efo_slim, pheno_slim, vertebrate_core, organ_slim
Membrane covering the brain and spinal cord. It is represented by a single layer in fishes, two in amphibians, reptiles and birds and three in mammals (named dura mater, arachnoid and pia mater). [TFD][VHOG]
In fishes, the meninges consist of a single membrane, the primitive meninx, wrapped around the brain and spinal cord. With the adoption of terrestrial life, the meninges doubled. In amphibians, reptiles, and birds, the meninges include a thick outer dura mater derived from mesoderm and a thin inner secondary meninx. (...) In mammals, the dura mater persists, but division of the secondary meninx yields both the arachnoid and the pia mater from ectomesoderm.[well established][VHOG]
Whereas cyclostomes and fishes only have a single envelope called the primitive meninx, amphibians have two layers, consisting of an outer dura mater which is extremely dense and protective, and a pia-arachnoid or secondary meninx which is more delicate and vascular. Mammals have three meninges: pia mater (which follows all the convolutions of the brain and is the most interior), the arachnoid layer (which is delicate and sends strands to the pia mater), and the dura mater (the outer, more protective meninx).