GI structure of the GI tract Flashcards
What are the basic layers of the GI tract?
Mucosa, submucosa, muscularis propria and adventitia.
What are the layers within the Mucosa from internal to external?
Epithelium, lamina propria and muscularis mucosa.
What is the lamina propria made of and what is its function?
Loose connective tissue providing vascular support to the epithelium.
What is the muscularis mucosa made of and what is its function?
Two layers of smooth muscle for the local movement of mucosa.
What is the sub mucosa made of and what is its function?
A loose connective tissue layer, with larger blood vessels, lymphatics, nerves, and can contain mucous secreting glands.
What is the muscularis propria made of and what is its function?
Two layers of smooth muscle the inner layer is circular, and the outer layer is longitudinal. For peristalsis of food down the gut.
What is another name for the muscularis propria?
The muscularis externa.
What is the adventitia made of and what is its function?
Loose connective tissue - covered by the visceral peritoneum. Contains blood vessels, lymphatics and nerves.
How many plexi are there in the GI tract and what are they called?
- The myenteric and submucosal plexi.
Where is the myenteric plexus found?
Between the inner and outer layers of the muscularis propria.
What is the function of the myenteric plexus?
It provides motor innervation to the muscularis externa of the GI tract. Both sympathetic and parasympathetic.
Where is the submucosal plexus found?
In the submucosa.
What is the function of the submucosal plexus?
Innervate cells in the epithelial layer and the smooth muscle of the muscularis mucosae. Only parasympathetic.
What are the accessory glands of the GI tract?
The liver, gall bladder, pancreas.
What type of glands is the liver?
Endocrine gland as release- lipids, glucose, proteins, glycoproteins and glycolipids into the bloodstream. Exocrine gland as secretes bile.
