digestive system two Flashcards
what is the function of the esophagus?
propel food to the stomach from the pharynx
what is the gross anatomy of the esophagus?
muscular tube that connects pharynx to stomach
what type of mucosa does the esophagus have?
nonkeratinized stratified squamous epithelium
what makes up the upper 1/3 of the esophagus’s muscularis?
skeletal muscle
what makes up the middle 1/3 of the esophagus’s muscularis?
skeletal and smooth muscle
what makes up the lower 1/3 of the esophagus’s muscularis?
smooth muscle only
what is the function of the stomach?
churns food (mechanical digestion) and mixes it with gastric juice (chemical digestion) to break it down into chyme
food and gastric juice mixed together
chyme
- connects to esophagus and duodenum
- located in the upper left part of the abdomen
- parts: cardia, fundus, body, pylorus
gross anatomy of the stomach
what type of mucosa does the stomach have?
simple columnar epithelium
how many layers of muscle is the esophagus’s muscularis?
two
what are located in the mucosa of the stomach?
gastric pits and glands
how many layers of smooth muscle are in the muscularis of the stomach?
three
what are the three layers of the stomach’s muscularis?
innermost oblique, inner circular, outer longitudinal layers
why does the stomach’s muscularis have three layers?
for churning and blending of the food bolus
what is the function of the small intestine?
finishes the chemical digestion process
- absorbs most (90%) of all nutrients
what are the three specific segments of the small intestine?
duodenum, jejunum, ileum
1st part, C-shaped
- receives chyme from stomach
- receives bile and pancreatic enzymes from liver and pancreas through duodenal papilla
duodenum
2nd part
- 2/5 of remaining small intestine
- huge surface area
jejunum
3rd part
- last 3/5 of small intestine
- connects to cecum of large intestine
- few folds but also MALT
ileum
what type of mucosa does the small intestine have?
simple columnar epithelium with goblet cells
what do the circular folds of the small intestine consist of?
mucosa and submucosa
- increase surface area so nutrients can be absorbed
- slow down chyme and allow it to mix with intestinal juices, allowing time for full nutrient absorption
function of circular folds
villi are only found on circular folds of what?
mucosa
- help increase surface area (along with microvillous border on the mucosa) and provide great distance for materials to be ingested and absorbed
function of villi
what is located in the center of each villus?
blood vessels and lacteal
transports dietary fats and lipids; type of lymphatic capillary
lacteal
what are the functions of the large intestine?
- absorption of water and electrolytes
- storage of undigested material (feces) until it can be expelled
what is the order of the segments of the large intestine?
cecum, vermiform appendix, ascending colon, transverse colon, descending colon, sigmoid colon, rectum, anal canal
connects to ileum
cecum
attaches to cecum
vermiform appendix
specific segment of the large intestine on the right side of body
ascending colon
runs from right to left side of the body
transverse colon
left side of body
descending colon
in pelvic cavtiy, s-shaped
sigmoid colon
terminal portion of large intestine
rectum and anal canal
feces leaves through this after going through anal canal
anus
what type of mucosa does the large intestine have?
simple columnar epithelium with goblet cells
how many layers of smooth muscle does the large intestine’s muscularis have?
two
what does the outer layer of the large intestine’s muscularis consist of?
teniae coli
what does the muscularis of the large intestine form?
haustra
