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Meckel's cartilage arises from the first pharyngeal arch. The dorsal end of each cartilage is connected with the ear-capsule and is ossified to form the malleus ; the ventral ends meet each other in the region of the mandibular symphysis , and are usually regarded as undergoing ossification to form that portion of the mandible which contains ...
Neural crest cells enter these arches where they contribute to features of the skull and facial skeleton such as bone and cartilage. [2] However, the existence of pharyngeal structures before neural crest cells evolved is indicated by the existence of neural crest-independent mechanisms of pharyngeal arch development. [3]
superior parathyroid glands and ultimobranchial body which forms the parafollicular C-Cells of the thyroid gland. Musculature and cartilage of larynx (along with the sixth pharyngeal arch). Nerve supplying these derivatives is Superior laryngeal nerve.
The mesenchymal cells within the mandibular prominence condense to form Meckel's cartilage. [2] ... hednk-032—Embryo Images at University of North Carolina
The theory of recapitulation, also called the biogenetic law or embryological parallelism—often expressed using Ernst Haeckel's phrase "ontogeny recapitulates phylogeny"—is a historical hypothesis that the development of the embryo of an animal, from fertilization to gestation or hatching (), goes through stages resembling or representing successive adult stages in the evolution of the ...
The face and neck development of the human embryo refers to the development of the structures from the third to eighth week that give rise to the future head and neck.They consist of three layers, the ectoderm, mesoderm and endoderm, which form the mesenchyme (derived form the lateral plate mesoderm and paraxial mesoderm), neural crest and neural placodes (from the ectoderm). [1]
By the tenth week, the portion of Meckel's cartilage which lies below and behind the incisor teeth is surrounded and invaded by the dermal bone (also known as the membrane bone). Somewhat later, accessory nuclei of cartilage make their appearance, as a wedge-shaped nucleus in the condyloid process and extending downward through the ramus;
The fetal membranes surround the developing embryo and form the fetal-maternal interface. [3] The fetal membranes are derived from the trophoblast layer (outer layer of cells) of the implanting blastocyst. [3] The trophoblast layer differentiates into amnion and the chorion, which then comprise the fetal membranes. [4]