exam 3- GI tract and cardiovascular Flashcards
primary digestive organs
mouth/oral cavity
pharynx
esophagus
stomach
small intestine
large intestine
rectum
anus
accessory digestive organs
teeth
tongue
salivary glands
liver
gallbladder
pancreas
duration of motility in oral cavity
voluntary control
duration of motility in esophagus
rapid pass
duration of motility in stomach
2.5 to 3 hours
duration of motility in small intestine
3-4 hours
duration of motility in colon
30-40 hours
where does absorption mostly occur?
small intestine
what is required for region specific digestion and the movement of food?
muscles! only muscles can generate force
muscles that are needed to region specific digestion
chewing or masticatory muscles (oral cavity)
tongue (oral cavity)
upper esophageal sphincter (skeletal musc)
upper esophagus (skeletal musc)
external anal sphincter (skeletal musc)
what are the 4 layers of the alimentary canal, starting with the outer layer?
serosa
muscularis
submucosa
mucosa
what does the mucosa consist of?
epithelium
lamina propria
muscularis mucosa
what does the submucosa consist of?
submucosal nerve plexus
what does the muscularis externa consist of?
circular muscle
myentric nerve plexus
longitudinal muscle
what system controls the GI activity?
enteric nervous system (ENS)
types of epithelial cells in the mucosa
protective epithelia
secretory epithelia
absorptive epithelia
protective epithelia is most abundant where
esophagus
secretory epithelia is most abundant where
throughout the entire GI tract.
mucus secreting cells (like goblet cells in small intestine)
enteroendocrine cells that secrete hormones
enterochromaffin-like (ECL) cells secrete neurotransmitters like histamine
what is the absorptive epithelial?
enterocytes, most abundant in small intestine
what is the lamina propria? (located in mucosa)
a connective tissue; immune cells, lacteal and capillaries
what is the muscularis mucosae? (located in mucosa)
a smooth muscle layer that is responsible for the folds and villi (which is what increases the surface area)
what is the submucosa?
a connective tissue layer that has arteries, veins and lymph vessels
what is the submucosal layer in the submucosa?
this layer senses the environment of the lumen and regulates the blood flow, epithelial cell function, and secretion from exocrine glands
what is the muscularis externa?
the layer between the submucosa and the serosa. it is made out of circular and longitudinal muscle in a perpendicular form. these layers of muscle give rise to the control of motility of digestive tract by controlling the contraction and relaxation times of the muscles.
