Structure of the wall Flashcards
What are the 4 layers of the alimentary canal
Mucosa (mucous membrane)
submucosa
muscle layer
serosa
Describe the structure of the mucosa (mucous membrane)
Surface epithelium, underlying connective tissue / smooth muscle
Folder in some regions with projections pushing into the tube (Lumen) of the canal
Describe the 2 functions of the mucosa (mucous membrane)
Increases surface area for absorption
Glands in the lining that secrete mucus , digestive enzymes
Describe what happens to the 4 layers of the alimentary canal?
Vary from region to region
Describe the structure of the submucosa
Much connective tissue
Glands, blood vessels, nerves
What is the function of the submucosa
Vessels provide resources to surrounding tissue and remove absorbed nutrients
Describe the structure of the muscularis
Has two layers of smooth muscle
What do they 2 layers of the muscularis provide?
the movement of the tube
What does the inner layer of the muscularis do?
Contraction reduces lumen diameter
What does the outer layer of the muscularis do?
Contraction shortens the tube length
What do coordinated contraction of the muscularis lead to?
Peristalsis
How many muscles does the stomach have?
Three
Where is the third muscle layer?
inside the inner layer
Where is the serous layer?
on outside of alimentary canal
What is beneath the serous layer?
Connective tissue
