Editing Endoderm (section)

{{Short description|Inner germ layer of embryonic development}}
{{Infobox embryology
| Name          = Endoderm
| Latin         =
| Image         = Embryonic_origin_of_endoderm.png
| Caption       = Tissues derived from endoderm.
| System        =
| CarnegieStage =
| Days          = 16
| Precursor     = [[Epiblast]]
| GivesRiseTo   = 
}}
'''Endoderm''' is the innermost of the three primary [[germ layer]]s in the very early [[embryo]]. The other two layers are the [[ectoderm]] (outside layer) and [[mesoderm]] (middle layer).<ref>Langman's Medical Embryology, 11th edition. 2010.</ref> Cells migrating inward along the [[archenteron]] form the inner layer of the [[gastrulation|gastrula]], which develops into the endoderm.<ref>{{cite journal |last1=Fukuda |first1=Kimiko |last2=Kikuchi |first2=Yutaka |title=Endoderm development in vertebrates: fate mapping, induction and regional specification |journal=Development, Growth and Differentiation |date=August 2005 |volume=47 |issue=6 |pages=343–355 |doi=10.1111/j.1440-169X.2005.00815.x |pmid=16109032 |s2cid=26241717 |url=https://onlinelibrary.wiley.com/doi/full/10.1111/j.1440-169X.2005.00815.x |access-date=10 March 2023 |language=en |issn=0012-1592|doi-access=free }}</ref>

The endoderm consists at first of flattened cells, which subsequently become columnar. It forms the [[epithelial]] lining of multiple systems.

In [[plant biology]], endoderm corresponds to the innermost part of the [[Cortex (botany)|cortex]] ([[Bark (botany)|bark]]) in young [[Shoot (botany)|shoots]] and young [[root]]s often consisting of a single [[Cell (biology)|cell]] layer. As the [[plant]] becomes older, more endoderm will [[Lignification|lignify]].