exam 1 digestive Flashcards
What are the 2 main groups of the digestive system?
gastrointestinal tract & accessory digestive organs
What is the GI tract?
a continuous tube from mouth to anus with food passing through its lumen (hollow center)
What are accessory digestive organs?
they participate in the digestive process but are not tubular (don’t have food passing through them)
What are the tissue layers that make up the entire GI tract (from deep to superficial)?
mucosa, submucosa, muscularis, & covering
What is the mucosa?
layer of mucous epithelium that lines the tract; the mucous produced by goblet cells protects this lining
What are the 3 parts of the mucosa?
mucous epithelium, lamina propria, & muscularis mucosa
What is the mucous epithelium?
deepest part of the mucosa; faces lumen
What is the lamina propria?
thin layer of connective tissue
What is the muscularis mucosa?
thin layer of smooth muscle; contracts to create ridges & folds in the mucosa
What is the submucosa?
thick layer of connective tissue containing blood vessels, glands, and nerves
What is the submucosal plexus?
formed by the nerves of the submucosa; controls the muscularis mucosa
What is the muscularis?
smooth muscle layers that contract to push food through the lumen of the GI tract; this is called peristalsis
What is the myenteric plexus?
embedded in the muscularis nerves; it is controlled by the ANS & allows for peristalsis; sympathetic stimulation slows this activity & parasympathetic stimulation speeds it up
What is the covering?
the outermost layer of the GI tract; 2 types which are serosa & adventitia
What is serosa?
thin moist serous membrane called peritoneum; it is folded into 2 surfaces which are parietal & visceral peritoneum
What is parietal peritoneum?
lines the walls of the abdominopelvic cavity
What is the visceral peritoneum?
adheres onto organs
What is inside the space between the parietal & visceral peritoneum?
serous fluid that provides lubrication and decreases friction as we move
What is adventitia?
tough connective tissue covering that binds/holds specific organs & nearby blood vessels in place
What organs are covered in adventitia?
pharynx, esophagus, rectum, & anal canal
What is the anterior boundary of the mouth cavity?
the labia which are the lips; they are covered in non-keratinized stratified epithelium which makes them more prone to chapping/sunburn
What is the red margin?
outer part of the lips; it is a deeper color due to visible blood vessels
What is the labial frenulum?
slender strand of mucous membrane that holds the lips to the gingivae (gums)
What is the superior boundary of the mouth cavity?
the roof of the mouth which is made of the hard & soft palates