chondrocranium


Also found in: Dictionary, Encyclopedia, Wikipedia.
Related to chondrocranium: dermatocranium, splanchnocranium, desmocranium

chondrocranium

 [kon″dro-kra´ne-um]
the cartilaginous cranial structure of the embryo from the seventh week to the middle of the third month, when it is a unified cartilaginous mass without clear boundaries indicating the limits of future bones.

chon·dro·cra·ni·um

(kon'drō-krā'nē-ŭm),
A cartilaginous cranium; the cartilaginous parts of the developing cranium.
[chondro- + G. kranion, skull]

chondrocranium

/chon·dro·cra·ni·um/ (-kra´ne-um) that part of the neurocranium formed by endochondral ossification and comprising the bones of the base of the skull.

chondrocranium

(kŏn′drō-krā′nē-əm)
n. pl. chondrocra·niums or chondrocra·nia (-nē-ə)
1. The cartilaginous cranium of an embryo before ossification.
2. A portion of the embryonic cranium forming the bones of the base of the skull and eventually undergoing ossification.

chondrocranium

Anatomy The bones of the base of the brain which are formed by endochondral ossification

chon·dro·cra·ni·um

(kon'drō-krā'nē-ŭm)
A cartilaginous cranium; the cartilaginous parts of the developing cranium.
[chondro- + G. kranion, skull]

chondrocranium

the cartilaginous original cranium surrounding the brain of the embryo, most of which is subsequently replaced by bone in further development.

chondrocranium

the cartilaginous cranial structure of the embryo in early pregnancy when it is a unified cartilaginous mass without clear boundaries indicating the limits of future bones.
References in periodicals archive ?
3, 4): In this stage the chondrocranium shows the configuration observed in the neonate.
In this stage, ossification is beginning in the chondrocranium.
5, 6): the two species are very similar in their chondrocranium, although there are slight differences between them (Table 1).
In the chondrocranium this is observed in the occipital and supraoccipital region; the prootic, otoccipital (opisthotic-exoccipital), basioccipital and basisphenoid are present.
In the orbitotemporal region of chondrocranium, the orbitosphenoid is observed (Table 1).
In general, Mabuya species included in this morphological study exhibit a complete chondrocranium, with the ethmoidal, orbitotemporal and occipital regions fully developed (Rao & Ramaswami 1952; Skinner 1973; Bellaris & Kamal 1981).
since the orbitosphenoid is not present in the fully formed chondrocranium of the embryo, but it is present in the adult stage (Rao & Ramaswami 1952).
Regarding the ossification of chondrocranium (Table 2), in Mabuya species, it starts in stage 39 (D&H); after that, all elements of chondrocranium are ossified and joined by synchondrosis (stage 40 D&H).
At this point in the evolutionary process, the palatoquadrate was completely fused with the chondrocranium to form a true autostylic jaw suspension, and it was covered almost entirely by dermal bone.