Gastrointestinal Tract Development - Revision history

Z8600021 at 00:36, 27 August 2020

2020-08-27T00:36:34Z

← Older revision		Revision as of 10:36, 27 August 2020
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	* '''Mapping of extrinsic innervation of the gastrointestinal tract in the mouse embryo'''{{#pmid:32690615\|PMID32690615}} "Precise extrinsic afferent (visceral sensory) and efferent (sympathetic and parasympathetic) innervation of the gut is fundamental for gut-brain crosstalk. Owing to the limitation of intrinsic markers to distinctively visualize the three classes of extrinsic axons, which intimately associate within the gut mesentery, detailed information on the development of extrinsic gut-innervating axons remains relatively sparse. Here, we mapped extrinsic innervation of the gut and explored the relationships among various types of extrinsic axons during embryonic development in mice. Visualization with characterized intrinsic markers revealed that visceral sensory, sympathetic, and parasympathetic axons arise from different anatomical locations, project in close association via the gut mesentery, and form distinctive innervation patterns within the gut from embryonic day {{ME10.5}} to {{ME16.5}}. Genetic ablation of visceral sensory trajectories results in the erratic extension of both sympathetic and parasympathetic axons, implicating that afferent axons provide an axonal scaffold to route efferent axons. Co-culture assay further confirmed the attractive effect of sensory axons on sympathetic axons. Taken together, our study provides key information regarding the development of extrinsic gut-innervating axons occurring through heterotypic axonal interactions and provides an anatomical basis to uncover neural circuit assembly in the gut-brain axis.Significance StatementUnderstanding the development of extrinsic innervation of the gut is essential to unravel the bidirectional neural communication between the brain and the gut. Here, with characterized intrinsic markers targeting vagal sensory, spinal sensory, sympathetic, and parasympathetic axons, respectively, we comprehensively traced the spatiotemporal development of extrinsic axons to the gut during embryonic development in mice. Moreover, in line with the somatic nervous system, pre-target sorting via heterotypic axonal interactions is revealed to play critical roles in patterning extrinsic efferent trajectories to the gut."		* '''Mapping of extrinsic innervation of the gastrointestinal tract in the mouse embryo'''{{#pmid:32690615\|PMID32690615}} "Precise extrinsic afferent (visceral sensory) and efferent (sympathetic and parasympathetic) innervation of the gut is fundamental for gut-brain crosstalk. Owing to the limitation of intrinsic markers to distinctively visualize the three classes of extrinsic axons, which intimately associate within the gut mesentery, detailed information on the development of extrinsic gut-innervating axons remains relatively sparse. Here, we mapped extrinsic innervation of the gut and explored the relationships among various types of extrinsic axons during embryonic development in mice. Visualization with characterized intrinsic markers revealed that visceral sensory, sympathetic, and parasympathetic axons arise from different anatomical locations, project in close association via the gut mesentery, and form distinctive innervation patterns within the gut from embryonic day {{ME10.5}} to {{ME16.5}}. Genetic ablation of visceral sensory trajectories results in the erratic extension of both sympathetic and parasympathetic axons, implicating that afferent axons provide an axonal scaffold to route efferent axons. Co-culture assay further confirmed the attractive effect of sensory axons on sympathetic axons. Taken together, our study provides key information regarding the development of extrinsic gut-innervating axons occurring through heterotypic axonal interactions and provides an anatomical basis to uncover neural circuit assembly in the gut-brain axis."

	* '''{{Stomach}} curvature is generated by left-right asymmetric gut morphogenesis'''{{#pmid:28242610\|PMID28242610}} "Left-right (LR) asymmetry is a fundamental feature of internal anatomy, yet the emergence of morphological asymmetry remains one of the least understood phases of organogenesis. Asymmetric rotation of the intestine is directed by forces outside the gut, but the morphogenetic events that generate anatomical asymmetry in other regions of the digestive tract remain unknown. Here, we show in mouse and Xenopus that the mechanisms that drive the curvature of the stomach are intrinsic to the gut tube itself. The left wall of the primitive stomach expands more than the right wall, as the left epithelium becomes more polarized and undergoes radial rearrangement. These asymmetries exist across several species, and are dependent on LR patterning genes, including Foxj1, Nodal and Pitx2 Our findings have implications for how LR patterning manifests distinct types of morphological asymmetries in different contexts."		* '''{{Stomach}} curvature is generated by left-right asymmetric gut morphogenesis'''{{#pmid:28242610\|PMID28242610}} "Left-right (LR) asymmetry is a fundamental feature of internal anatomy, yet the emergence of morphological asymmetry remains one of the least understood phases of organogenesis. Asymmetric rotation of the intestine is directed by forces outside the gut, but the morphogenetic events that generate anatomical asymmetry in other regions of the digestive tract remain unknown. Here, we show in mouse and Xenopus that the mechanisms that drive the curvature of the stomach are intrinsic to the gut tube itself. The left wall of the primitive stomach expands more than the right wall, as the left epithelium becomes more polarized and undergoes radial rearrangement. These asymmetries exist across several species, and are dependent on LR patterning genes, including Foxj1, Nodal and Pitx2 Our findings have implications for how LR patterning manifests distinct types of morphological asymmetries in different contexts."

Z8600021 at 00:36, 27 August 2020

2020-08-27T00:36:00Z

← Older revision		Revision as of 10:36, 27 August 2020
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			* '''Mapping of extrinsic innervation of the gastrointestinal tract in the mouse embryo'''{{#pmid:32690615\|PMID32690615}} "Precise extrinsic afferent (visceral sensory) and efferent (sympathetic and parasympathetic) innervation of the gut is fundamental for gut-brain crosstalk. Owing to the limitation of intrinsic markers to distinctively visualize the three classes of extrinsic axons, which intimately associate within the gut mesentery, detailed information on the development of extrinsic gut-innervating axons remains relatively sparse. Here, we mapped extrinsic innervation of the gut and explored the relationships among various types of extrinsic axons during embryonic development in mice. Visualization with characterized intrinsic markers revealed that visceral sensory, sympathetic, and parasympathetic axons arise from different anatomical locations, project in close association via the gut mesentery, and form distinctive innervation patterns within the gut from embryonic day {{ME10.5}} to {{ME16.5}}. Genetic ablation of visceral sensory trajectories results in the erratic extension of both sympathetic and parasympathetic axons, implicating that afferent axons provide an axonal scaffold to route efferent axons. Co-culture assay further confirmed the attractive effect of sensory axons on sympathetic axons. Taken together, our study provides key information regarding the development of extrinsic gut-innervating axons occurring through heterotypic axonal interactions and provides an anatomical basis to uncover neural circuit assembly in the gut-brain axis.Significance StatementUnderstanding the development of extrinsic innervation of the gut is essential to unravel the bidirectional neural communication between the brain and the gut. Here, with characterized intrinsic markers targeting vagal sensory, spinal sensory, sympathetic, and parasympathetic axons, respectively, we comprehensively traced the spatiotemporal development of extrinsic axons to the gut during embryonic development in mice. Moreover, in line with the somatic nervous system, pre-target sorting via heterotypic axonal interactions is revealed to play critical roles in patterning extrinsic efferent trajectories to the gut."

	* '''{{Stomach}} curvature is generated by left-right asymmetric gut morphogenesis'''{{#pmid:28242610\|PMID28242610}} "Left-right (LR) asymmetry is a fundamental feature of internal anatomy, yet the emergence of morphological asymmetry remains one of the least understood phases of organogenesis. Asymmetric rotation of the intestine is directed by forces outside the gut, but the morphogenetic events that generate anatomical asymmetry in other regions of the digestive tract remain unknown. Here, we show in mouse and Xenopus that the mechanisms that drive the curvature of the stomach are intrinsic to the gut tube itself. The left wall of the primitive stomach expands more than the right wall, as the left epithelium becomes more polarized and undergoes radial rearrangement. These asymmetries exist across several species, and are dependent on LR patterning genes, including Foxj1, Nodal and Pitx2 Our findings have implications for how LR patterning manifests distinct types of morphological asymmetries in different contexts."		* '''{{Stomach}} curvature is generated by left-right asymmetric gut morphogenesis'''{{#pmid:28242610\|PMID28242610}} "Left-right (LR) asymmetry is a fundamental feature of internal anatomy, yet the emergence of morphological asymmetry remains one of the least understood phases of organogenesis. Asymmetric rotation of the intestine is directed by forces outside the gut, but the morphogenetic events that generate anatomical asymmetry in other regions of the digestive tract remain unknown. Here, we show in mouse and Xenopus that the mechanisms that drive the curvature of the stomach are intrinsic to the gut tube itself. The left wall of the primitive stomach expands more than the right wall, as the left epithelium becomes more polarized and undergoes radial rearrangement. These asymmetries exist across several species, and are dependent on LR patterning genes, including Foxj1, Nodal and Pitx2 Our findings have implications for how LR patterning manifests distinct types of morphological asymmetries in different contexts."

Z8600021 at 08:23, 18 November 2019

2019-11-18T08:23:56Z

Z8600021 at 05:00, 23 Ocak 2019

2019-01-23T05:00:04Z

← Older revision		Revision as of 15:00, 23 Ocak 2019
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	The '''mesenteries''' of the GIT are generated from the common dorsal mesentery, with the ventral mesentry contributing to the '''lesser omentum''' and '''falciform ligament'''.		The '''mesenteries''' of the GIT are generated from the common dorsal mesentery, with the ventral mesentry contributing to the '''lesser omentum''' and '''falciform ligament'''.

	Note the duodenum is commonly divided into 4 anatomical parts.		Note the duodenum is commonly divided into 4 anatomical sequential parts (superior, descending, horizontal, ascending).

	:'''Links:''' {{Intestine}} \| {{mesentery}}		:'''Links:''' {{Intestine}} \| {{mesentery}}

Z8600021 at 04:57, 23 Ocak 2019

2019-01-23T04:57:37Z

← Older revision		Revision as of 14:57, 23 Ocak 2019
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	===Midgut===		===Midgut===
	[[File:Gray0986.jpg\|thumb\|midgut herniation]]		[[File:Gray0986.jpg\|thumb\|midgut herniation]]
	~~From beneath the stomach the initial portion of the small intestine, the duodenum, and the associated pancreas now lie.~~

	~~Much~~ of the '''midgut is herniated''' at the umbilicus external to the abdomen through development. A key step in development is the rotation of this midgut that must occur to place the GIT in the correct abdominal position with its associated mesentry. The GIT itself differentiates to form significantly different structures along its length: oesophagus, ~~stomach~~, ~~duodenum~~, ~~jejunum, iliem (small intestine)~~, colon (~~large intestine~~).		The middle embryonic division of gastrointestinal tract contributing the small intestine (including duodenum beneath distal bile duct opening), cecum, appendix, ascending colon, and part of the transverse colon (right half to two thirds). The midgut blood supply is the superior mesenteric artery.

	The '''~~mesentries~~''' of the GIT are generated from the common dorsal ~~mesentry~~, with the ventral mesentry contributing to the '''lesser omentum''' and '''falciform ligament'''.
			Much of the '''midgut is herniated''' at the umbilicus external to the abdomen through development. A key step in development is the rotation of this midgut that must occur to place the GIT in the correct abdominal position with its associated mesentry. The GIT itself differentiates to form significantly different structures along its length: oesophagus, stomach, duodenum, jejunum, ilium (small intestine), colon (large intestine).


			The '''mesenteries''' of the GIT are generated from the common dorsal mesentery, with the ventral mesentry contributing to the '''lesser omentum''' and '''falciform ligament'''.

			Note the duodenum is commonly divided into 4 anatomical parts.

	:'''Links:''' {{Intestine}} \| {{mesentery}}		:'''Links:''' {{Intestine}} \| {{mesentery}}

Z8600021 at 04:53, 23 Ocak 2019

2019-01-23T04:53:51Z

← Older revision		Revision as of 14:53, 23 Ocak 2019
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	The '''mesentries''' of the GIT are generated from the common dorsal mesentry, with the ventral mesentry contributing to the '''lesser omentum''' and '''falciform ligament'''.		The '''mesentries''' of the GIT are generated from the common dorsal mesentry, with the ventral mesentry contributing to the '''lesser omentum''' and '''falciform ligament'''.

			:'''Links:''' {{Intestine}} \| {{mesentery}}
	===Hindgut===		===Hindgut===

Z8600021 at 03:34, 23 Ocak 2019

2019-01-23T03:34:31Z

← Older revision		Revision as of 13:34, 23 Ocak 2019
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	===Hindgut===		===Hindgut===
	The {{hindgut}} region initially contributes the {{cloaca}}, that will contribute the distal transverse colon, descending colon, sigmoid colon, rectum. Located at the hindgut inferior end is the cloacal membrane, an early transient structure, that degenerates after cloacal septation.

	The ~~initial~~ {{cloaca}} is the ~~common early~~ hindgut space ~~that~~ will later become partitioned by a septum into a dorsal gastrointestinal component (rectum) and ventral renal/genital component ~~(urogenital sinus~~).		The final embryonic division of gastrointestinal tract consisting initially of the {{cloaca}} snd extending to the cloacal membrane. The hindgut contributes part of the transverse colon (left half to one third), descending colon, sigmoid colon, rectum, part of anal canal (superior), urinary epithelium (bladder and most urethra).


			The initial {{cloaca}} space will later become partitioned by a septum into a dorsal gastrointestinal component (rectum) and ventral urogenital sinus (renal/genital component).

Z8600021 at 03:16, 23 Ocak 2019

2019-01-23T03:16:31Z

← Older revision		Revision as of 13:16, 23 Ocak 2019
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	{{GIT cartoons}}		{{GIT cartoons}}

	==Gastrointestinal Tract Divisions ==		==Gastrointestinal Tract Divisions==
	[[File:GIT_blood_supply.jpg\|left\|300px]] During the 4th week the 3 distinct divisions ({{foregut}}, {{midgut}} and {{hindgut}}) ~~can be first seen extending~~ the length of the embryo from ~~buccopharyngeal~~ membrane to cloacal membrane and ~~connected at the {{midgut}} to the yolk sac. These~~ will ~~3 divisions~~ contribute ~~all~~ components of the GIT ~~and~~ are also later defined by ~~their~~ vascular (~~arterial~~) supply to each divisions.		[[File:GIT_blood_supply.jpg\|left\|300px]] During the 4th week the 3 distinct divisions ({{foregut}}, {{midgut}} and {{hindgut}}) extend the length of the embryo from oral membrane to cloacal membrane and will contribute different components of the GIT. These 3 divisions are also later anatomically defined by the vascular (artery) supply to each of theses divisions.

	The large mid-gut is generated by lateral embryonic folding which "pinches off" a pocket of the yolk sac, the 2 compartments continue to communicate through the vitelline duct.		The large mid-gut is generated by lateral embryonic folding which "pinches off" a pocket of the yolk sac, the 2 compartments continue to communicate through the vitelline duct.
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	The oral cavity ('''mouth''') is formed following breakdown of the buccopharyngeal membrane (oropharyngeal, oral membrane) and contributed to mainly by the pharynx lying within the pharyngeal arches. The opening of the GIT means that it contains amniotic fluid, which is also swallowed later in development.		The oral cavity ('''mouth''') is formed following breakdown of the buccopharyngeal membrane (oropharyngeal, oral membrane) and contributed to mainly by the pharynx lying within the pharyngeal arches. The opening of the GIT means that it contains amniotic fluid, which is also swallowed later in development.

	~~<div id="Foregut"></div>~~
	===Foregut===		===Foregut===
	[[File:Gitbpm.jpg\|thumb\|Stage {{CS11}} foregut]] From the oral cavity the next portion of the foregut is initially a single gastrointestinal (oesophagus) and respiratory (trachea) common tube, the pharynx which lies behind the heart. Note that the respiratory tract will form from a ventral bud arising at this level.		[[File:Gitbpm.jpg\|thumb\|Stage {{CS11}} foregut]]
			First embryonic division of gastrointestinal tract, extending from the oral (buccopharyngeal) membrane and contributing oesophagus, {{stomach}}, duodenum (to bile duct opening), {{liver}}, biliary apparatus (hepatic ducts, {{gallbladder}}, and bile duct), and {{pancreas}}. The forgut blood supply is the celiac artery (trunk) excluding the pharynx, lower respiratory tract, and most of the oesophagus.


			From the oral cavity the next portion of the foregut is initially a single gastrointestinal (oesophagus) and respiratory (trachea) common tube, the pharynx which lies behind the heart. Note that the respiratory tract will form from a ventral bud arising at this level.

	* Oral cavity		* Oral cavity
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	* Stomach		* Stomach

	~~<div id="Midgut"></div>~~
	===Midgut===		===Midgut===
	[[File:Gray0986.jpg\|thumb\|midgut herniation]]		[[File:Gray0986.jpg\|thumb\|midgut herniation]]
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	The '''mesentries''' of the GIT are generated from the common dorsal mesentry, with the ventral mesentry contributing to the '''lesser omentum''' and '''falciform ligament'''.		The '''mesentries''' of the GIT are generated from the common dorsal mesentry, with the ventral mesentry contributing to the '''lesser omentum''' and '''falciform ligament'''.

	~~<div id="Hindgut"></div>~~
	===Hindgut===		===Hindgut===
	The {{hindgut}} region initially contributes the {{cloaca}}, that will contribute the distal transverse colon, descending colon, sigmoid colon, rectum. Located at the hindgut inferior end is the cloacal membrane, an early transient structure, that degenerates after cloacal septation.		The {{hindgut}} region initially contributes the {{cloaca}}, that will contribute the distal transverse colon, descending colon, sigmoid colon, rectum. Located at the hindgut inferior end is the cloacal membrane, an early transient structure, that degenerates after cloacal septation.

Z8600021 at 02:50, 23 Ocak 2019

2019-01-23T02:50:55Z

← Older revision		Revision as of 12:50, 23 Ocak 2019
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	{{GIT cartoons}}		{{GIT cartoons}}

	== ~~3 GIT divisions~~ ==		==Gastrointestinal Tract Divisions ==
	[[File:GIT_blood_supply.jpg\|left\|300px]] During the 4th week the 3 distinct ~~portions~~ (~~fore-~~, ~~mid-~~ and ~~hind-gut~~) ~~extend~~ the length of the embryo and will contribute ~~different~~ components of the GIT~~. These 3 divisions~~ are also later defined by ~~the~~ vascular (~~artery~~) supply to each ~~of theses~~ divisions.		[[File:GIT_blood_supply.jpg\|left\|300px]] During the 4th week the 3 distinct divisions ({{foregut}}, {{midgut}} and {{hindgut}}) can be first seen extending the length of the embryo from buccopharyngeal membrane to cloacal membrane and connected at the {{midgut}} to the yolk sac. These will 3 divisions contribute all components of the GIT and are also later defined by their vascular (arterial) supply to each divisions.

	The large mid-gut is generated by lateral embryonic folding which "pinches off" a pocket of the yolk sac, the 2 compartments continue to communicate through the vitelline duct.		The large mid-gut is generated by lateral embryonic folding which "pinches off" a pocket of the yolk sac, the 2 compartments continue to communicate through the vitelline duct.
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	The oral cavity ('''mouth''') is formed following breakdown of the buccopharyngeal membrane (oropharyngeal, oral membrane) and contributed to mainly by the pharynx lying within the pharyngeal arches. The opening of the GIT means that it contains amniotic fluid, which is also swallowed later in development.		The oral cavity ('''mouth''') is formed following breakdown of the buccopharyngeal membrane (oropharyngeal, oral membrane) and contributed to mainly by the pharynx lying within the pharyngeal arches. The opening of the GIT means that it contains amniotic fluid, which is also swallowed later in development.

			<div id="Foregut"></div>
	===Foregut===		===Foregut===
	[[File:Gitbpm.jpg\|thumb\|Stage {{CS11}} foregut]] From the oral cavity the next portion of the foregut is initially a single gastrointestinal (oesophagus) and respiratory (trachea) common tube, the pharynx which lies behind the heart. Note that the respiratory tract will form from a ventral bud arising at this level.		[[File:Gitbpm.jpg\|thumb\|Stage {{CS11}} foregut]] From the oral cavity the next portion of the foregut is initially a single gastrointestinal (oesophagus) and respiratory (trachea) common tube, the pharynx which lies behind the heart. Note that the respiratory tract will form from a ventral bud arising at this level.
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	* Stomach		* Stomach

			<div id="Midgut"></div>
	===Midgut===		===Midgut===
	[[File:Gray0986.jpg\|thumb\|midgut herniation]]		[[File:Gray0986.jpg\|thumb\|midgut herniation]]
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	The '''mesentries''' of the GIT are generated from the common dorsal mesentry, with the ventral mesentry contributing to the '''lesser omentum''' and '''falciform ligament'''.		The '''mesentries''' of the GIT are generated from the common dorsal mesentry, with the ventral mesentry contributing to the '''lesser omentum''' and '''falciform ligament'''.

			<div id="Hindgut"></div>
	===Hindgut===		===Hindgut===
	The {{hindgut}} region initially contributes the {{cloaca}}, that will contribute the distal transverse colon, descending colon, sigmoid colon, rectum. Located at the hindgut inferior end is the cloacal membrane, an early transient structure, that degenerates after cloacal septation.		The {{hindgut}} region initially contributes the {{cloaca}}, that will contribute the distal transverse colon, descending colon, sigmoid colon, rectum. Located at the hindgut inferior end is the cloacal membrane, an early transient structure, that degenerates after cloacal septation.

Z8600021 at 21:03, 19 December 2018

2018-12-19T21:03:49Z

@@ Line 302: / Line 302: @@
 ===Search PubMed===
-Search Mar 2007 "gastrointestinal tract development" '''29,361''' reference articles of which '''3,494''' were reviews.
+{|
 '''Search Pubmed:''' [http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&cmd=search&term=gastrointestinal%20tract%20development Gastrointestinal Tract Development]

← Older revision		Revision as of 18:23, 18 November 2019
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	[[File:Gray0982a.jpg\|thumb\|300px\|The early gastrointestinal tract.]]		[[File:Gray0982a.jpg\|thumb\|300px\|The early gastrointestinal tract.]]
	[[File:Stage11_sem4.jpg\|thumb\|300px\|Human head ([[Week 4]], [[Carnegie stage 11\|Stage 11]]) showing buccopharyngeal membrane breakdown.]]		[[File:Stage11_sem4.jpg\|thumb\|300px\|Human head ([[Week 4]], [[Carnegie stage 11\|Stage 11]]) showing buccopharyngeal membrane breakdown.]]
	The {{gastrointestinal tract}} (GIT) arises initially during the process of gastrulation from the ~~[[E#~~endoderm~~\|endoderm]]~~ of the trilaminar embryo (week 3) and extends from the ~~[[B#buccopharyngeal membrane\|~~buccopharyngeal membrane]] to the {{cloacal membrane}}. The tract and associated organs later have contributions from all the germ cell layers.		The {{gastrointestinal tract}} (GIT) arises initially during the process of gastrulation from the {{endoderm}} of the trilaminar embryo (week 3) and extends from the {{buccopharyngeal membrane}} to the {{cloacal membrane}}. The tract and associated organs later have contributions from all the germ cell layers.


	During the 4th week three distinct regions (fore-, mid- and hind-gut) extend the length of the embryo and will contribute different components of the GIT. The large mid-gut is generated by lateral embryonic folding which "pinches off" a pocket of the yolk sac, the 2 compartments continue to communicate through the vitelline duct.		During the 4th week three distinct regions (fore-, mid- and hind-gut) extend the length of the embryo and will contribute different components of the GIT. The large mid-gut is generated by lateral embryonic folding which "pinches off" a pocket of the {{yolk sac}}, the 2 compartments continue to communicate through the vitelline duct.


	The oral cavity (mouth) is formed following breakdown of the buccopharyngeal membrane (oropharyngeal or oral membrane) and contributed to mainly by the pharynx lying within the pharyngeal ~~arches~~ (More? [[Head Development]]). Loss of buccopharyngeal membrane opens the tract to amniotic fluid through the remainder of development, and during the fetal period is actively swallowed.		The oral cavity (mouth) is formed following breakdown of the {{buccopharyngeal membrane}} (oropharyngeal or oral membrane) and contributed to mainly by the pharynx lying within the {{pharyngeal arch}}es (More? [[Head Development]]). Loss of buccopharyngeal membrane opens the tract to amniotic fluid through the remainder of development, and during the fetal period is actively swallowed.


	From the oral cavity the next portion of the foregut is initially the pharynx, a single gastrointestinal (oesophagus) and respiratory (trachea) common tube, that lies behind the heart. Note that the respiratory tract will form from a ventral bud arising at this level (More? {{respiratory}}).		From the oral cavity the next portion of the foregut is initially the pharynx, a single gastrointestinal ({{oesophagus}}{{) and respiratory (trachea) common tube, that lies behind the heart. Note that the respiratory tract will form from a ventral bud arising at this level (More? {{respiratory}}).

	This current page provides an introductory overview, use the links below for descriptions of specific components and regions as well as developmental abnormalities.		This current page provides an introductory overview, use the links below for descriptions of specific components and regions as well as developmental abnormalities.
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	{{Gastrointestinal Tract Links}}		{{Gastrointestinal Tract Links}}

	Note that in historic texts the term ''entoderm'' is used to describe '''endoderm''' and other terminology may also differ from current descriptions.		Note that in historic texts the term ''entoderm'' is used to describe '''{{endoderm}}''' and other terminology may also differ from current descriptions.

	[[File:Endoderm_cartoon.jpg\|600px\|link=One Minute Embryology#Endoderm Development]]		[[File:Endoderm_cartoon.jpg\|600px\|link=One Minute Embryology#Endoderm Development]]
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	* '''Stomach curvature is generated by left-right asymmetric gut morphogenesis'''{{#pmid:28242610\|PMID28242610}} "Left-right (LR) asymmetry is a fundamental feature of internal anatomy, yet the emergence of morphological asymmetry remains one of the least understood phases of organogenesis. Asymmetric rotation of the intestine is directed by forces outside the gut, but the morphogenetic events that generate anatomical asymmetry in other regions of the digestive tract remain unknown. Here, we show in mouse and Xenopus that the mechanisms that drive the curvature of the stomach are intrinsic to the gut tube itself. The left wall of the primitive stomach expands more than the right wall, as the left epithelium becomes more polarized and undergoes radial rearrangement. These asymmetries exist across several species, and are dependent on LR patterning genes, including Foxj1, Nodal and Pitx2 Our findings have implications for how LR patterning manifests distinct types of morphological asymmetries in different contexts."		* '''{{Stomach}} curvature is generated by left-right asymmetric gut morphogenesis'''{{#pmid:28242610\|PMID28242610}} "Left-right (LR) asymmetry is a fundamental feature of internal anatomy, yet the emergence of morphological asymmetry remains one of the least understood phases of organogenesis. Asymmetric rotation of the intestine is directed by forces outside the gut, but the morphogenetic events that generate anatomical asymmetry in other regions of the digestive tract remain unknown. Here, we show in mouse and Xenopus that the mechanisms that drive the curvature of the stomach are intrinsic to the gut tube itself. The left wall of the primitive stomach expands more than the right wall, as the left epithelium becomes more polarized and undergoes radial rearrangement. These asymmetries exist across several species, and are dependent on LR patterning genes, including Foxj1, Nodal and Pitx2 Our findings have implications for how LR patterning manifests distinct types of morphological asymmetries in different contexts."

	* '''The Digestive Tract in Human Embryos Between Carnegie Stages 11 and 13'''{{#pmid:26995337\|PMID26995337}} "The digestive tract was initially formed by a narrowing of the yolk sac, and then several derived primordia such as the pharynx, lung, stomach, liver, and dorsal pancreas primordia differentiated during CS12 (21-29 somites) and CS13 (≥ 30 somites). The differentiation of four pairs of pharyngeal pouches was complete in all CS13 embryos. The respiratory primordium was recognized in ≥ 26-somite embryos and it flattened and then branched at CS13. The trachea formed and then elongated in ≥ 35-somite embryos. The stomach adopted a spindle shape in all ≥ 34-somite embryos, and the liver bud was recognized in ≥ 27-somite embryos. The dorsal pancreas appeared as definitive buddings in all but three CS13 embryos, and around these buddings, the small intestine bent in ≥ 33-somite embryos. In ≥ 35-somite embryos, the small intestine rotated around the cranial-caudal axis and had begun to form a primitive intestinal loop, which led to umbilical herniation."		* '''The Digestive Tract in Human Embryos Between Carnegie Stages {{CS11}} and {{CS13}}'''{{#pmid:26995337\|PMID26995337}} "The digestive tract was initially formed by a narrowing of the yolk sac, and then several derived primordia such as the pharynx, lung, stomach, liver, and dorsal pancreas primordia differentiated during {{CS12}} (21-29 somites) and CS13 (≥ 30 somites). The differentiation of four pairs of pharyngeal pouches was complete in all {{CS13}} embryos. The respiratory primordium was recognized in ≥ 26-somite embryos and it flattened and then branched at {{CS13}}. The trachea formed and then elongated in ≥ 35-somite embryos. The stomach adopted a spindle shape in all ≥ 34-somite embryos, and the liver bud was recognized in ≥ 27-somite embryos. The dorsal pancreas appeared as definitive buddings in all but three CS13 embryos, and around these buddings, the small intestine bent in ≥ 33-somite embryos. In ≥ 35-{{somite}} embryos, the small intestine rotated around the cranial-caudal axis and had begun to form a primitive intestinal loop, which led to umbilical herniation."

	\|}		\|}