endoderm Flashcards
(9 cards)
What is the endoderm?
The innermost layer of the intestinal tube
It arises during gastrulation and forms the gut tube.
What are the two types of endoderm in mammals?
- TRIPOBLASTS: have endo, ecto, and mesoderm
- DIPOBLASTS: have endo and ectoderm
This classification is based on the number of germ layers.
What role does the endoderm play in the body?
- Forms an internal surface (gut) for nutrient absorption
- Allows food to be brought close to cells for digestion
This is essential for energy acquisition.
How is the gut tube formed?
Through lateral and longitudinal folding
This process is critical for the development of the digestive system.
What is FOXA2?
A transcription factor expressed in all endoderm cells
It plays a significant role in gut development.
What does folding and regionalization create in the gut?
- FOREGUT
- HINDGUT
These regions are essential for the formation of various digestive structures.
What structures are formed from the juxtapositions of endoderm and ectoderm?
- Lungs
- Oropharyngeal membrane (future mouth)
- Liver
- Cloacal membrane (future anus)
- Pancreas
These structures are vital for respiratory and digestive functions.
What are the consequences of longitudinal folding?
- Brings endoderm into contact with ectoderm and mesoderm
- Enables inductive signaling
This signaling is important for organ development.
Fill in the blank: The endoderm undergoes changes from _______ to cuboidal to pseudo stratified.
simple squamous
