Chondrocranium

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Chondrocranium
Details
Identifiers
Latin chondrocranium
TA98 A02.1.00.009
TA2 357
FMA 76621
Anatomical terminology

The chondrocranium (or cartilaginous neurocranium ) is the primitive cartilaginous skeletal structure of the fetal skull that grows to envelop the rapidly growing embryonic brain. [1]

Contents

The chondrocranium in different species can vary greatly, but in general it is made up of four components, the sphenoids, occipitals, otic capsules, and nasal capsules. [2]

In humans, the chondrocranium begins forming at 28 days from mesenchymal condensations and is fully formed between week 7 and 9 of fetal development. While the majority of the chondrocranium is succeeded by the bony skull, some components do persist into adulthood. [1] In cartilaginous fishes (e.g. sharks and rays) and agnathans (e.g. lampreys and hagfish), the chondrocranium persists throughout life. [3] Embryologically, the chondrocranium represents the basal cranial structure, and lays the base for the formation of the endocranium. [4]

Divisions

The portion of the chondrocranium that is associated with the notochord is termed the chordal chondrocranium and is formed from mesodermally-derived mesenchyme. The more rostral portion of the chondrocranium that lie anterior to the notochord constitutes the prechordal chondrocranium, and is derived primarily from neural crest-derived mesenchyme. [1]

See also

Related Research Articles

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References

  1. 1 2 3 Salentijn, L. Biology of Mineralized Tissues: Prenatal Skull Development, Columbia University College of Dental Medicine post-graduate dental lecture series, 2007
  2. Kardong, Kenneth V. (2015). Vertebrates: Comparative Anatomy, Function, Evolution. New York: McGraw-Hill Education. p. 701.
  3. Kent, G.C & Miller, L. (1997): Comparative Anatomy of the Vertebrates. Wm. C. Brown Publishers. ISBN   0-697-24378-8.
  4. Romer, Alfred Sherwood; Parsons, Thomas S. (1977). The Vertebrate Body. Philadelphia, PA: Holt-Saunders International. pp. 216–247. ISBN   0-03-910284-X.