Digestive System II Flashcards
peritoneum
- serous membrane that lines abdominopelvic cavity
- support and covers most of the organs in this cavity
peritoneal cavity
- space btwn the parietal and visceral layers of peritoneum
- contains small amounts of serous fluid
parietal peritoneum
-attached to the abdominal pelvic wall
visceral peritoneum
-attached to the organs of the digestive tract
greater omentum
-suspended from the inferior curvature of the stomach
lesser omentum
-attaches the lesser curvature of the stomach to the liver
mesentery
-attaches the small intestine to posterior abdominal wall
mesocolon
-attaches the large intestine to posterior abdominal wall
falciform ligament*
-attaches liver to inferior diaphragm and anterior body wall
which organs are retroperitoneal
- pancreas
- kidney
- portion of the duodenum
- ascending & descending colon
stomach location
- upper left quadrant
- btwn esophagus and small intestine
stomach structure
divided into:
- cardia
- fundus
- body
- pylorus
layers in stomach wall
- muscularis externa
- rugae
- gastric glands
stomach: muscularis externa composition
-simple columnar epithelium
stomach: submucosa
-nerves and blood vessels
stomach: muscularis
-3 layers of smooth muscle
stomach: serosa
-CT
stomach: rugae structure
-folds of mucosal layers
stomach: rugae function
- permits stomach to distend
- increase SA for secretion and digestion
- disappear as stomach expands
stomach gastric glands: chief cells
-produces inactive pepsinogen –> pepsin for protein digestion
stomach gastric glands: parietal cells
- produces HCL which dec. the pH of stomach contents
- produces intrinsic factors required for B12 absorption
stomach gastric glands: mucous cells
- aka goblet cells
- secrete protective mucous
stomach gastric glands: enteroendocrine cells
- secrete hormones which influence digestive organs
- i.e. G cells secrete gastrin (inc. GI activity)
stomach gastric glands: sphincters
-regulate flow of food
stomach gastric glands: cardiac sphincter
-junction of stomach and esophagus
stomach gastric glands: pyloric sphincter
- made of smooth muscle
- junction of stomach and duodenum
- regulated by parasympathetic
stomach function
- mechanical mixing of food & production of “chyme”
- initiates major protein digestion
- storage of chyme until it passes into the duodenum
- minimal absorption (i.e. drugs, alcohol)
chyme
- acidic pasty material
- food leaving the stomach
small intestine location
- extends from pyloric sphincter to large intestine
- occupies central & lower portion of abdominal cavity
small intestine duodenum
- retroperitoneal
- C-shaped first 10 inches of small intestine
small intestine duodenum: duodenal papilla*
-opening through which bile and enzymes enter the duodenum
small intestine duodenum: brunner’s glands
- secrete alkaline solution
- protects intestinal lining of acidic chyme
small intestine: jejunum
- middle section
- slightly larger lumen
small intestine: ileum
- third region of small intestine
- contains peyer’s patches
define peyer’s patches*
-clusters of lymphatic tissue
small intestine function*
- major site of chemical digestion
- mechanical mixing
- major site for absorption of nutrients
- propels undigested nutrients or materials to large intestine
small intestine: plicae circulares
- deep folds of mucosa
- inc. SA for digestion & absorption
- doesn’t disappear as intestine expands
small intestine: villi
- small finger-like projections
- inc. SA
- capillary network
- lacteal
small intestine: lacteals
-transports fats to lymphatics
small intestine: microvilli
-microscopic processes on columnar cells
small intestine: intestinal cells
- secrete enzymes
- found in crypts of lieberkuhn
- promote absorption
large intestine location
begins at end of ileum in LRQ–>superiorly to liver–>left to spleen–>descends on left to pelvis–>end at anus
large intestine: cecum
- dilated pouch at junction of small intestine& lagre intestine
- LRQ
- ileocecal valve: guards opening
large intestine: ascending colon
-right side
large intestine: transverse colon
-passes from right to left
large intestine: descending colon
-left side
large intestine: sigmoid colon
- S-shaped
- from left side to center of body
large intestine: rectum
- in midline
- leads to anal canal
large intestine: anal canal
-passageway leading to the anus
large intestine: sphincters
-guard openings
large intestine: internal anal sphincter
-smooth muscle
large intestine: external anal sphincter
-skeletal muscle
large intestine: taeniae coli
-long strip of smooth muscle
large intestine: haustra
-sac-like regions
large intestine: epiploic appendages
-fat-filled pouches
large intestine: hepatic flexure
-right celic flexure
large intestine: splenic flexure
-left colic flexure
large intestine function
- absorption of water
- formation, storage and expulsion of feces
- contains “normal flora” (bacteria)
- manufacture vitamins:: fat soluble A, D, E, K
appendix location
- LRQ
- retro-cecal
appendix structure
- finger-like projections
- blind pouch
- contains lymphatic tissue
