Surface ectoderm

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Surface ectoderm
Ectoderm.png
Organs derived from ectoderm.
Details
Precursor Ectoderm
Identifiers
FMA 87656
Anatomical terminology

The surface ectoderm, AKA external ectoderm, is one of the two early embryonic divisions of the ectoderm. The other early division of the ectoderm is the neuroectoderm.

Contents

The surface ectoderm develops into the following structures:

See also

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<span class="mw-page-title-main">Nasal placode</span>

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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, neural crest and neural placodes. The paraxial mesoderm forms structures named somites and somitomeres that contribute to the development of the floor of the brain and voluntary muscles of the craniofacial region. The lateral plate mesoderm consists of the laryngeal cartilages. The three tissue layers give rise to the pharyngeal apparatus, formed by six pairs of pharyngeal arches, a set of pharyngeal pouches and pharyngeal grooves, which are the most typical feature in development of the head and neck. The formation of each region of the face and neck is due to the migration of the neural crest cells which come from the ectoderm. These cells determine the future structure to develop in each pharyngeal arch. Eventually, they also form the neurectoderm, which forms the forebrain, midbrain and hindbrain, cartilage, bone, dentin, tendon, dermis, pia mater and arachnoid mater, sensory neurons, and glandular stroma.

References

PD-icon.svgThis article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)