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, (sometimes called Entoderm) is one of the germ layers formed during animal embryogenesis. Cells migrating inward along the archenteron form the inner layer of the gastrula, which develops into the endoderm.

The endoderm consists at first of flattened cells, which subsequently become columnar. It forms the epithelial lining of 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, the epithelium of the auditory tube and tympanic cavity, of the trachea, bronchi, and alveoli of the lungs, of the urinary bladder and part of the urethra, and that which lines the follicles of the thyroid gland and thymus.

Contents 1 Production 2 Additional images 3 See also 4 Notes 5 References

[edit] Production

The following chart shows the products produced by the endoderm.

Germ Layer	Category	Product
Endoderm	General[1]	Gastrointestinal tract
Endoderm	General	Respiratory tract
Endoderm	General	Endocrine glands and organs (liver and pancreas)

The Endoderm has differentiated into distinguishable organs as early as 5 weeks of embryonic development.

[edit] Additional images

Section through the embryo.

Section through ovum imbedded in the uterine decidua

[edit] See also

• Ectoderm
• Germ layer
• Histogenesis
• Mesoderm
• Organogenesis
• Endodermal sinus tumor

[edit] Notes

[edit] References

Look up endoderm in Wiktionary, the free dictionary.

• Evers, Christine A., Lisa Starr. Biology:Concepts and Applications. 6th ed. United States:Thomson, 2006. ISBN 0-534-46224-3.

v • d • e Developmental biology > Human embryogenesis (development of embryo) and development of fetus First three weeks Week 1 Fertilization · Egg activation · Zygote · Cleavage · Morula · Blastula (Blastomere) · Blastocyst · Inner cell mass Week 2 (Bilaminar) Hypoblast · Epiblast Week 3 (Trilaminar) Germ layers Archenteron/Primitive streak (Primitive pit, Primitive knot/Blastopore, Primitive groove) · Gastrula/Gastrulation · Regional specification Ectoderm Surface ectoderm · Neuroectoderm · Somatopleure · Neurulation · Neural crest Endoderm Splanchnopleure Mesoderm Chorda- · Paraxial (Somite/Somitomere/Sclerotome/Myotome/Dermatome) · Intermediate · Lateral plate (Intraembryonic coelom, Splanchnopleure/Somatopleure) Extraembryonic/ uterus Trophoblast (Cytotrophoblast, Syncytiotrophoblast) Blastocoele · Yolk sack/exocoelomic cavity · Heuser's membrane · Extraembryonic coelom · Vitelline duct Umbilical cord (Umbilical artery, Umbilical vein, Wharton's jelly) · Allantois Placenta · Decidua (Decidual cells) · Chorionic villi/Intervillous space · Gestational sac (Amnion/Amniotic sac/Amniotic cavity, Chorion) Histogenesis Programmed cell death (Apoptosis) · Stem cells · Germ line development Organogenesis Limb development: Limb bud · Apical ectodermal ridge/AER other structures: Eye development · Cutaneous structure development · Heart development · Development of the urinary and reproductive organs (Some dates are approximate—see Carnegie stages and a timeline.)

v • d • e Germ layers Germ Layers Ectoderm • Endoderm • Mesoderm Production Histogenesis • Organogenesis

This 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.