Chondrocranium

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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]

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 in most higher vertebrates, 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.[2] Embryologically, the chondrocranium represents the basal cranial structure, and lays the base for the formation of the endocranium in higher vertebrates.[3]

Divisions[edit]

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[edit]

References[edit]

  1. ^ a b c Salentijn, L. Biology of Mineralized Tissues: Prenatal Skull Development, Columbia University College of Dental Medicine post-graduate dental lecture series, 2007
  2. ^ Kent, G.C & Miller, L. (1997): Comparative Anatomy of the Vertebrates. Wm. C. Brown Publishers. ISBN # 0-697-24378-8.
  3. ^ Romer, Alfred Sherwood; Parsons, Thomas S. (1977). The Vertebrate Body. Philadelphia, PA: Holt-Saunders International. pp. 216–247. ISBN 0-03-910284-X.