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]
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]
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]
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]
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]
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]