64 notecards = 16 pages (4 cards per page)
List digestive system functions:
List the organs of the alimentary canal:
List the accessory organs of the GI:
Mechanical breakdown of food in the GI involves:
Propulsion of things through the GI involves:
Absorption of nutrients primarily occurs where?
Absorption of water primarily occurs where?
Innermost layer of epithelial cells that
List the structures located in the mucosa
Part of the mucosa with a rich lining of mucus secreting cells
Part of the mucosa that is connective tissue and mucosa-associated lymphoid tissue (MALT) containing lymphocytes, plasma cells, and macrophages
Part of the mucosa that produces local movement
Dense connective tissue that contains part of the enteric nerve system; elastic fibers that allow stretching
Responsible for segmentation and peristalsis (longitudinal/circular muscle), contains part of the enteric nerve system
Outermost protective layer, visceral peritoneum, consisting of squamous cells.
T/F: The oral cavity, pharynx, and rectum have adventitia instead of serosa
Local constriction of the small intestine and, to a lesser extent, the large intestine to mix food w digestive juices and increase exposure to the intestinal wall
Alternating waves of contraction and relaxation of smooth muscle to propel food through the GI tract
Contract and relax to control movement or holding of luminal content
T/F: Segmentation and peristalsis are phasic, while sphincters are tonic
What kind of muscle is involved in segmentation?
Describe the "Law of the Gut"
Peristaltic reflex pushes intestinal contents from the oral to the aboral direction
Describe the three steps in peristalsis
List the three major types of GI control
T/F: The ENS possesses afferent, efferent , and interneurons and has an abundance of short reflexes.
List the two major plexuses of the ENS
Which plexus is responsible for contraction and relaxation of GI tract smooth muscle (GI motility)
Myenteric plexus (Auerbach's)
Which plexus is responsible for secretory and absorptive functions as well as local blood flow?
Submucosal plexus (Meissner's)
When stimulated, the main effects of the Myenteric plexus (Auerbach's) are:
Where is the Myenteric plexus (Auerbach's) plexus located?
bw circular and longitudinal muscle layers along length of gut
Where is the Submucosal plexus (Meissner's) located?
Submucosa of small and large intestine
T/F: Intrinsic primary afferent nerves involved in sight, smell, taste, or the thought of food eventually acts through the extrinsic primary nerves and can induce GI secretions. This is why you may salivate at the thought of your favorite food
Summarize the movement of the GI tract:
Which NT almost always inhibits GI activity?
Neuropeptide from tachykinin family that serves as a cotransmitter w ACh. Stimulates smooth muscle contrations
High concentrations of 5HT in the gut can lead to:
Stimuli responsible for the release of 5HT:
List the roles of 5HT
T/F: All 5HT receptors are GPCR except 5HT2 which is a ligand-gated ion channel
Which 5HT receptors are in GI tract on enterocytes, enteric neurons, GI smooth muscle, and immune cells?
Which 5HT receptor is found on intrinsic primary sensory afferents and can cause depolarization of the afferent nerves when stimulated?
Which 5HT receptor is located on intrinsic and extrinsic primary sensory afferents and stimulation causes depolarization of these nerves?
Which 5HT receptor is located presynaptically on post-ganglionic nerves to ENHANCE release of ACh and can cause an increase in GI secretions. Also involved in peristaltic reflex
Which 5HT receptor releases inhibitory substances such as VIP and NO
Summarize GI motility in the submucosal plexus ascending pathway:
Summarize GI motility in the submucosal plexus descending pathway:
Summarize GI motility in the myenteric plexus (longitudinal muscle)
T/F: Longitudinal contraction prevents bulging
Summarize GI motility in the myenteric plexus (long reflex)
List the three classes of hormone signaling in GI:
List the roles of GI hormones:
Hormones are ____________ secreted by ______________
Peptides; enteroendocrine cells
Gastric inhibitory Peptide (GIP)
List the pancreatic secretions
List the liver secretions:
Where is bile stored?
__________ stimulates bicarb secretion (therefore bile) from the liver and bicarb from the pancrease
_______ causes the contraction of gallbladder and inhibits stomach emptying
CCK relaxes sphincter of _______
A concretion in the gallbladder or a bile duct, composed chiefly of a mixture of cholesterol, calcium bilirubinate, and ca carbonate; may cause jaundice and acute pancreatitis