- Endoderm
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Endoderm Organs derived from endoderm. Blastodermic vesicle of Vespertilio murinus. (Endoderm labeled as 'entoderm'.) Gray's subject #6 49 Days 16 Precursor hypoblast Gives rise to splanchnopleure MeSH Endoderm Endoderm is one of the three primary germ cell layers in the very early embryo. The other two layers are the ectoderm (outside layer) and mesoderm (middle layer), with the endoderm as the intermost layer.[1] Cells migrating inward along the archenteron form the inner layer of the gastrula, which develops into the endoderm.[citation needed]
The endoderm consists at first of flattened cells, which subsequently become columnar. It forms the epithelial lining of multiple systems.[citation needed]
Contents
Production
The following chart shows the products produced by the endoderm.
Layer Category System General[2] Gastrointestinal tract. the entire alimentary canal except part of the mouth, pharynx and the terminal part of the rectum (which are lined by involutions of the ectoderm), the lining cells of all the glands which open into the digestive tube, including those of the liver and pancreas General Respiratory tract the trachea, bronchi, and alveoli of the lungs General Endocrine glands and organs the lining of the follicles of the thyroid gland and thymus Auditory system the epithelium of the auditory tube and tympanic cavity Urinary system the urinary bladder and part of the urethra Liver and pancreas cells are believed to derive from a common precursor.[3]
The Endoderm has differentiated into distinguishable organs as early as 5 weeks of embryonic development.
Additional images
See also
References
- ^ Langman's Medical Embryology, 11th edition. 2010.
- ^ The General category denotes that all or most of the animals containing this layer produce the adjacent product.
- ^ Zaret KS (October 2001). "Hepatocyte differentiation: from the endoderm and beyond". Curr. Opin. Genet. Dev. 11 (5): 568–74. doi:10.1016/S0959-437X(00)00234-3. PMID 11532400. http://linkinghub.elsevier.com/retrieve/pii/S0959-437X(00)00234-3.
Developmental biology > Human embryogenesis (development of embryo) and development of fetus (TE E2.0) First three
weeksWeek 1Fertilization · Oocyte activation · Zygote · Cleavage · Morula · Blastula (Blastomere) · Blastocyst · Inner cell massWeek 2
(Bilaminar)Week 3
(Trilaminar)Archenteron/Primitive streak (Primitive pit, Primitive knot/Blastopore, Primitive groove) · Gastrula/Gastrulation · Regional specification · Embryonic discEndodermSplanchnopleuric mesenchymeChorda- · Paraxial (Somite/Somitomere) · Intermediate · Lateral plate (Intraembryonic coelom, Splanchnopleuric mesenchyme/Somatopleuric mesenchyme)Human cell types / list derived primarily from endoderm Foregut enteroendocrine: G cell · D cell · ECL cell
exocrine: Gastric chief cell · Parietal cell
Foveolar cellCentroacinar cell · Pancreatic stellate cellPharyngeal pouch Hindgut/cloaca Urothelial cellsThis article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.
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