PHYS 1 motility of the GI tract Flashcards
major activity along the GI tract?
involves what actions? which do what?
Rate?
layers of the GI tract?
enteric nervous system
plexus?
each controls what?
reflexes?
circular and longitudinal smooth muscle
circular action?
longitudinal action?
types of contraction?
(ahead of wave)
smooth muscle electrical signals
type of waves?
action potentials?
tension related to electrical activity?
relationship between membrane potentials and contraction of smooth muscle?
spiked potentials?
2 types of smooth muscle contraction?
where and when do these happen?
Depolarization and action potentials
stimulated by?
inhibited by?
influence of ANS
PNS
SNS
pacemaker cells of GI motility?
how does this pacemaker action happen?
chewing reflex causes?
most muscles during this are innervated by?
how does this work?
Phases of swallowing
(voluntary vs. involuntary)?
phases?
distribution of smooth and skeletal muscle
pharyngeal phase
voluntary or involuntary?
steps in this phase?
esophageal phase of swallowing
controlled by?
steps?
relationship to vagotomy?
involuntary swallowing reflex?
what coordinates?
steps?
pressure changes along esophagus during swallowing
proximal vs distal end?
UES and LES usually what?
relaxation of stomach?
GERD
occurs when? (common ex)
what happens?
complications?
Achalasia?
what is it?
why does it happen?
Gastric contractions
anatomical divisions?
physiological divisions?
layers of stomach?
extrinsic innervation?
intrinsic innervation?
receptive relaxation
what does it allow?
what is it? (stomach)
role of hormone?
mixing contractions of stomach
primary (__________)?
type?
start where? spread where?
force and velocity?
max frequency?
mixing contractions of the stomach
_____pulsion?
does what?
propels bolus back but can also have subsequent wave that has a higher contraction point than previous (pictures on right)
regulation of gastric contractions
what branches?
rold of MMCs in GI
what are MMCs?
intervals? during?
mediated by?
inhibited when?
regulation of gastric emptying
gastric emptying accomplished by?
takes how long?
rate increased by?
regulation of gastric emptying
gastric emptying
rate decreased by?
negative feedback from duodenum called? causes?
entero-gastric reflex
what is it?
via what mechanisms?
entero-gastric reflex
symptoms of gastric motility issues?
causes?
treatment?
gastroparesis?
common in?
cause?
symptoms?
small intestine motility
key for?
3 specifics?
types of general contractions?
segmental contractions of small intestine
what type of movement?
electrical activity of the small intestine
always present?
stimulated by?
what initiates contraction?
parts of SI and frequency?
propulsive contractions of small intestine
what type of contrations?
what contracts?
contractile ring?
innervation?
regulation of peristaltic contractions in SI
boxes what is released which causes what?
what cells or tissues?
SNS vs PSNS?
stimulators?
inhibitors?
vomiting reflex
coordinated by?
impulses transmitted via? to where?
events? (7)
Ileocecal junction
controls what?
distention of ileum vs colon?
innervation of large intestine?
ENS
plexus? where? innervate what?
PSNS
nerves? innervate what part?
SNS
what innervates what?
Somatic pudendal nerves?
LI types of contractions?
mass movement via?
occur when over what?
how often?
stimulate what?
motility in LI important for?
poor motility?
excess?
Motility of rectum and anal canal
rectum fills in what way? via?
rectosphincteric reflex?
external anal sphincter?
rectosphincteric reflex and defecation
whats under neural control? which branches?
pathways that mediate? if damaged?
Hirschsprung disease
cause?
result?
at birth causes?
other symptoms?
older children symptoms?
treatment?
GI reflexes
name of reflex?
what does it cause?
summary motility patterns
Esophagus
stomach
SI
LI
summary of hormonal regulation
go for it by yourself first
Gastrin, CCK, Insulin, Motilin, Serotonin, Secretin, Glucagon
Things to know forever
ENS works with? to control what?
know the path of food bolus and general concept of reflexes especially swallowing and defecation
conditions and diseases associated with a loss of motility
