Embryonic Origins
The splanchnocranium is derived from the neural crest cells (also responsible for the development of the neurocranium or, teeth and adrenal medulla) or from scleratone found in the somite block of the mesoderm. As with the neurocranium, in Chondricthyes and other cartilaginous vertebrates, they are not replaced via endochondral ossification. In tetrapods, such as amphibians and reptiles, the columella connecting to the tympanum is derived from the splanchnocranium. In mammals, the splanchnocranium derives the bones of the middle ear, the malleus, the incus and stapes.
Read more about this topic: Facial Skeleton
Famous quotes containing the words embryonic and/or origins:
“Quintilian [educational writer in Rome around A.D. 100] thought that the earliest years of the child’s life were crucial. Education should start earlier than age seven, within the family. It should not be so hard as to give the child an aversion to learning. Rather, these early lessons would take the form of play—that embryonic notion of kindergarten.”
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“Lucretius
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smiling carves dreams, bright cells
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