GI tract Flashcards
What is the gastro intestinal tract
tube like part of the digestive system going from mouth to anus
Where does ingestion take place
Mouth and oesophagus
Where does propulsion occur
Throughout the GI tract via peristalsis
Where does digestion occur
Mouth, stomach and small intestine
Where does nutrient and water absorption occur
Within small and large intestines
Defecation is what?
Removal of wastes
what type of tissue lines the gitract
epithelial
the structure of the wall consists of how many distinct layer
four
What is the innermost layer of the GI tract wall
Mucosa
Mucosa secretes what
Mucus, digestive enzymes and hormones
What does mucosa absorb
Nutrients
What type of tissue does mucosa possess and what is the function of this tissue
Possesses MALT (mucosa associated lymphoid tissue) and protects against infection
Where is muscularis mucosae located and what is it
A thin layer of smooth muscle cells within the mucosa itself
Purpose of the muscularis mucosae
Prevents adherent material from building up and clogging the GI tract
What is the muscularis mucosae responsible for
For folding the epithelium of the small intestine into finger-like projections called villi
What does the sub mucosa have
Rich supplies of blood vessels, nerves, lymph vessels and lymph nodes
What does the muscularis externa compromise of
Inner circular and outer longitudinal layers of smooth muscle, 2 layers
The layers of smooth muscle in the muscularis are essential for what
Propelling the contents of the GI tract forward and assisting in digestion
What is segmentation
Mixing movement
What is propulsive movement
Peristalsis
What is the outermost layer of the wall
Serosa
What is the serosa composed of and what is its function
Connective tissue and is protective
What 6 things is the GI tract divided into
Oral cavity, oropharynx, oesophagus, stomach, small intestine, large intestine
