4LE Physio HM Flashcards
What are the components of the GI system?
Mouth Pharynx Esophagus Salivary glands Pancreas Stomach Liver Gallbladder Small Intenstines Deudenum, Jejunum, Ileum Colon/Large Intestines Anus
Mouth and Pharynx Esophagus Stomach Small Intenstines Deudenum, Jejunum, Ileum Colon/Large Intestines Anus
What are the accessory organs in the GI system?
Mouth and Pharynx Esophagus Salivary glands Pancreas Stomach Liver Gallbladder Small Intenstines Deudenum, Jejunum, Ileum Colon/Large Intestines Anus
Salivary glands
Pancreas
Liver
Gallbladder
What are the physiological processes of GIT
Motility
Secretion
Absorption
Digestion
What are the secretory part of the GI system?
Mouth and Pharynx Esophagus Salivary glands Pancreas Stomach Liver Gallbladder Small Intenstines Deudenum, Jejunum, Ileum Colon/Large Intestines Anus
Mucosa of SI Large Intestines Esophagus Pharynx Salivary glands Liver Pancreas
What neuroligic system of the body facilitates digestion and absorption that is most concerend with the process if digestion?
- Autonomic Nervous system - parasympathetic
- Enteric Nervous system - sympathetic
- Somatic Nervous System
Autonomic Nervous system - parasympathetic
It is a type of ANS that Inhibits control of the GIT
Sympathetic
Parasympathetic
Sympathetic
It is the dominant neural control of the GIT
- Autonomic Nervous system
- Enteric Nervous system
- Somatic Nervous System
ANS
90% of GIT is mostly composed of?
SKELETAL MUSCLE
SMOOTH MUSCLE
GLANDS
CARDIAC MUSCLE
SMOOTH MUSCLE
The ANS is usually most functional in?
SKELETAL MUSCLE
SMOOTH MUSCLE
GLANDS
CARDIAC MUSCLE
glands, cardiac muscle and smooth muscle
Urge to vomit, nausea, abdominal pain and other SOS signals makes the ____ to communicate to the brain .
- Autonomic Nervous system
- Enteric Nervous system
- Somatic Nervous System
ENS
Neurological system that is for voluntary control of skeletal ms at the external anal sphincter, mouth and pharynx and the upper 1/3 of the esophagus
- Autonomic Nervous system
- Enteric Nervous system
- Somatic Nervous System
Somatic Nervous System
THE_____ facilitases localized contraction and secretions that can respond to the changes that are felt by the sensory neurons
- Autonomic Nervous system
- Enteric Nervous system
- Somatic Nervous System
ENS
interneuron projecting caudally and functions for muscle relaxation
Ach-
GCRP
somastatin
substance P
somastatin
they are release by bipolar neurons and functions in pain pathways and modulate inflammation
histamine neuropeptide Y gamma-aminobutyric acid somastatin serotonin
substance P
GCRP
Ach-
two types of electrical waves that excites the GIT smooth ms
- true action potential
- not action potential
Slow wave
Spike potential
Slow wave - not action potential
Spike potential - true action potential
It occur when the RMP of GI smooth ms becomes more positive that -40mV
Slow wave - not action potential
Spike potential - true action potential
Spike potential
Inhibit motor and secretory function of GIT
Sympathetic NS
Parasympathetic NS
Sympathetic NS
stimulates motor and secretory function of GIT
Sympathetic NS
Parasympathetic NS
Parasympathetic NS
Parasympathetic and sympathetic nerve system both carry _____ nerve fibers
afferent
efferent
afferent
Type of neurotransmitter that is in the myenteric plexus and contracts the smooth ms
histamine neuropeptide Y gamma-aminobutyric acid somastatin serotonin
gamma - aminobutyric acid
it is an interneuron meurotransmitter
histamine neuropeptide Y gamma-aminobutyric acid somastatin serotonin
serotonin
An inhibitory neurotransmitter from synapsing adregenic neuron
histamine neuropeptide Y gamma-aminobutyric acid somastatin serotonin
neuropeptide Y
Pacemaker cells found in the CT interstitium near the smooth ms cells and is the pacemaker sites of slow waves
myenteric plexus Interstitial cells of Cajal (ICC) Cholecystikinin GIP Sensing Cells
Interstitial cells of Cajal (ICC)
True action potential found in the GIT that excites muscle contraction
Slow wave
Spike potential
Spike potential
When does the frequency of spike potential increases?
the higher the slow wave potential rises
the higher the slow wave potential decreases
the lower the slow wave potential rises
the loweer the slow wave potential decreases
the higher the slow wave potential rises
Pathway of basic electrical rhythm
a) ICC- interstitial cells of cajal -> Slow waves -> smooth muscle contraction -> spike potential
b) Slow waves -> spike potential -> ICC- interstitial cells of cajal -> smooth muscle contraction
c) ICC- interstitial cells of cajal -> Slow waves -> spike potential -> smooth muscle contraction
d) ICC- interstitial cells of cajal -> spike potential -> Slow waves -> smooth muscle contraction
e) ICC- interstitial cells of cajal -> smooth muscle contraction-> Slow waves -> spike potential
ICC- interstitial cells of cajal -> Slow waves -> spike potential -> smooth muscle contraction
Main endocrine hormones
myenteric plexus Interstitial cells of Cajal (ICC) Cholecystikinin GIP Sensing Cells
Cholecystikinin - gall bladder contraction - gastrointestinal motility - pancreatic exocrine secretion Secretin - pancreatic exocrine secretion GIP -incretin activity Motilin - gastrointestinal motility
Examples of paracrine
histanime neuropeptide Y gamma-aminobutyric acid somastatin serotonin
histanime
somatostatin
Function of Paracrine - processes where a chem messenger/regulatory peptide is released from ____ in the intestinal wall
myenteric plexus Interstitial cells of Cajal (ICC) Cholecystikinin GIP Sensing Cells
sensing cell
A mechanical digestion of food to facilitates enzymatic digestion
mastication or chewing
Saliva is secreted by:
parotid gland (largest salivary gland)
sublingual gland
submandibular gland
parotid gland (largest salivary gland)
sublingual gland
submandibular gland
List major charactersitic of saliva
- large vol relative to mass (1-1.5L per day)
- low K conc
- high osmolarity (quite diluted)
- contains specialized inorganic materials
- large vol relative to mass (1-1.5L per day)
- high K conc
- low osmolarity (quite diluted)
- contains specialized organic materials
salivary component involved in lubrication
mucins proline-rich glycoproteins Cholecystikinin GIP water amylase defensins lipase ribunuclease
mucins proline-rich glycoproteins water amylase defensins
salivary component involved in growth
epidermal growth fator EGF
Trasforming growth factor (TGF) - a, b
fibroblast GF - FGF
insulin-like gf
epidermal growth fator EGF
Trasforming growth factor (TGF) - a, b
fibroblast GF - FGF
insulin-like gf
salivary component involved in buffering
water gustin mucin bicarbonate phosphate ions proteins
bicarbonate
phosphate ions
proteins
salivary component involved in digestion
mucins proline-rich glycoproteins Cholecystikinin GIP water amylase defensins lipase ribunuclease
amylase lipase ribonuclease protease water mucin
salivary component involved in taste
water gustin mucin bicarbonate phosphate ions proteins
water
gustin
salivary component involved in speech
water gustin mucin bicarbonate phosphate ions proteins
water
mucin
a ) Phases in swallowing or deglutition
b) reflex mechanism where nasopharynx close to prevent regurgitation
c) palatopharyngeal folds are pulled medially to form passage for foor to move into the pharynx
d) primary peristalsis - follows swallow and its secondary peristalsis - food remain stuck in the esophagus (ENS senses this condition)
Oral Phase
pharyngeal phase
Esophageal phase
a) Oral Phase
pharyngeal phase
Esophageal phase
b) pharyngeal phase
c) pharyngeal phase
d) Esophageal phase
Prevents reflux of acidic gastric contents into the esophagus
VIP - vasoactive intestinal polypeptide
LES - lower esophageal sphincter
NO - nitric oxide
Interstitial cells of Cajal (ICC)
LES - lower esophageal sphincter
receptive relaxation is mediated by vagus nerve secretes _______ when food is brought by peristalsis into esophagus
VIP - vasoactive intestinal polypeptide LES - lower esophageal sphincter NO - nitric oxide Interstitial cells of Cajal (ICC) Fundus of the stomach
VIP - vasoactive intestinal polypeptide
NO - nitric oxide
Other than LES, this also relaxes to accommodate more food
VIP - vasoactive intestinal polypeptide LES - lower esophageal sphincter NO - nitric oxide Interstitial cells of Cajal (ICC) Fundus of the stomach
Fundus of the stomach
Closes the LES - lower esophageal sphincter
Coffee without the caffeine
GERD - gastroesophageal reflux disease
enterogastric reflex
Coffee without the caffeine
LES unable to maintain normal tone
Coffee without the caffeine
GERD - gastroesophageal reflux disease
enterogastric reflex
GERD - gastroesophageal reflux disease
In gastric motility, what occurs during
a. ) fundus enlarge as food enters the stomach
b. ) food in the body and antrum increases contraction: peristalsis and retropulsion
c. ) chyme is propelled through the polyric sphinctier into the intestines
d) synchronous contractions of fundus , body and antrum
e. fundus becomes quiescent, stores food
between meals mixing emptying storage right after meal
a. storage
b. mixing
c. emptying
d. between meals
e. right after meal
contractions that goes towards the caudal end
enterogastric reflex
mixing reflex
lactating reflex
Peristaltic
Peristaltic
excitatory hormone in gastric emptying
mucus bicarbonate gastrin pepsin HCl Ach
gastrin
Cholecystokinin and secretin are what type of gastric emptying hormone?
excitatory
inhibitory
inhibitory
local reflex taht streched the antrum and increase volume in gastric emptying
excitatory
inhibitory
excitatory
example of a inhibitory gastric emptying local reflex
enterogastric reflex mixing reflex lactating reflex vomiting reflexes Peristaltic
enterogastric reflex
They are for protection of gastric mucosa against acidic and peptic luminal environment
mucus bicarbonate gastrin pepsin HCl Ach
mucus and bicarbonate
It is consist of a gel-forming glycoprotein (mucins) and protective layer of epithelium
mucus bicarbonate gastrin pepsin HCl Ach
mucus
NaHCO3 a neutrulizer is increased by ____ and decreased by _____
stress PNS aspirin-NSAIDs sympathetics (NE, Epi) mucosal irritation prostaglandins empty stomach smoking
increased by: mucosal irritation PNS prostaglandins empty stomach
decreased by: stress sympathetics (NE, Epi) aspirin-NSAIDs smoking
Main digestive enzyme
mucus bicarbonate gastrin pepsin HCl Ach
pepsin
Pepsins secreted as inactive ___________ is activated by decrease in pH (HCl).
gastric and intestinal phases
mucus and bicarbonate
pepsinogen I and II
pepsinogen I and II
_____ provides optimal pH for pepsins, it kills ingested bacteria and it stimulates the flow of bile
mucus bicarbonate gastrin pepsin HCl Ach
HCl
Increased Vit B12 leads to increase ____ secretion
mucus bicarbonate gastrin pepsin HCl Ach
HCl
It binds Vit B12 and aids its absorption in the ileum
Intrinsic Factor (IF) Extrinsic Factor
Intrinsic Factor (IF)
Stimulus for all the phases in the mechanisms of stimulating gastric secretions
mucus bicarbonate gastrin pepsin HCl Ach
Ach
Gastrin
Chewing and swallowing are stimuls for what?
gastric phase
cephalical phase
intestinal phase
gastric and intestinal phases
Distension and digested protein are stimulus for?
gastric phase
cephalical phase
intestinal phase
gastric and intestinal phases
Organs of the body that have all the phases of gastric secretion
esophagus stomach pancrease small intestine colon
stomach and pancreas
What ar the phases of gastric secretion
gastric phase
cephalical phase
intestinal phase
gastric
cephalic
intestinal
TRUE or FALSE
In the cephalic phase
a. presence of food in the mouth inhibits gastric secretion
b. increase in appetite also increase stimulation
c. increase sympathetic stimulation (stress ) mucsla lining decreases
a. FALSE, it stimulates gastric secretion
b. TRUE
c. TRUE
Accounts for 60% (1.5L) of total gastric secretion associated with eating meals
gastric phase
cephalical phase
intestinal phase
gastric phase
Accounts for 10% of total gastric secretion associated with eating meals
gastric phase
cephalical phase
intestinal phase
intestinal phase
Distended intestines ________ gastric emptying
stimulate
inhibit
inhibits
increase or decrease ??? cephalic phase a. loss of appetite b. stimulation of taste and smell receptors c. sight and thought of food d. depression gastric phase e. excessive acidity in stomach f. stomach distention g. emotion upset h. food chemicals intestinal phase i. presence of partially digested food in the duodenum when stomach begins to empty j. presence of acidic, hyper or hypotonic chime/irritants in the duodenum
a. dec
b. inc
c. inc
d. dec
e. dec
f. inc
g. dec
h. inc
i. inc
j. dec
The three agonist of parietal cells in gastric secretion
gastrin bicarbonate histamine pepsin ranitidin Ach
gastrin
histamine
acetylcholine
blocks H2 receptors wherein 90% of acid production is inhibited
gastrin bicarbonate histamine pepsin ranitidin Ach
ranitidin
type of receptor
acetycholine: __
histamine: __
gastrin: __
somatostatin: ___
H2 receptor
muscarinic receptor
inhibitor; secreted by D cells
CCKB receptor
: muscarinic receptor
: H2 receptor
: CCKB receptor
: inhibitor; secreted by D cells
Taking Lozec premanently inhibits the ______ but the stomach produces new parietal cells daily so these drugs are taken daily to dec acidity and not totally terminated
H-K pumps
Na-glucose cotransporter
Na-K pumps
H-K pumps
Is triggered by stimulation of vomiting center (medulla), chemoreceptor trigger zone and duedenal receptor (intestines)
enterogastric reflex mixing reflex lactating reflex vomiting reflexes Peristaltic
vomiting reflexes
Sequence of events during emesis / vomiting
- reverse peristalsis
- LES relaxes
- forceful contraction of abdominal muscle - increased intraabdominal pressure
- pyloric sphincter and stomach relax
- forced inspiration on closed glottis - dec intrathoracic pressure
- UES relaxes
- reverse peristalsis
- pyloric sphincter and stomach relax
- forced inspiration on closed glottis - dec intrathoracic pressure
- forceful contraction of abdominal muscle - increased intraabdominal pressure
- LES relaxes
- UES relaxes
Continous vomiting results in:
- increase acidity in lumen
- decrease acidity in lumen
- increase activity of H-K pump
- decrease activity of H-K pump
- metabolic alkalosis
- metabolic acidosis
- decrease acidity in lumen
- increase activity of H-K pump
- metabolic alkalosis (loss of H+)
what are the origin of vomitus and determine their determined by color
stomach
intestines - yellowish and greenish
stomach
intestines - yellowish and greenish
movements of intestines that does mixing contractions is __a__ and movement that does propulsive contractions is __b__?
segmentation
perstalsis
a. segmentation
b. perstalsis
keeps the bacterial concentration low in the small intestines
ileocecal junction
It occurs in between meals.
migrating myoelectric complex
In migrating myoelectrical complex, peristalsis occurs in _____
circular to longitudal muscle contraction
_____ and _____ inhibit small intestines motility
secretin ; glucagon
This is a localized stimulation of the SI at a certain point will produce a contraction at the area near the oral end and relaxation at the area near the anal end
Peristaltic reflex
A response where it removes blockage and distention occur
intestinointestinal reflex
The stomach stimulates the ileum to increase motility
gastroileal reflex
A reflex , when stomach is full the ileum will increase motility, if the ileum is full the stomach stop moving
ileogastric reflex
in anointestinal reflex, a full anus inhibits ____
intestinal motility
the only part of the large intestine taht is complete in all the layering would be ____
the part near the rectum
What are the principal function of the colon?
- absorption of water and electrolytes from the chyme to form solid feces
- storage of fecal matter until it can be expelled
Large intestine motility is regulated primarily by the
ENS - neural pathways
The only movement when we are asleep which is more prominent in the sigmoid colon and rectum
rectal motor complex
Phases of migrating myoelectric complex
phase 1: Quiescent pahse - there is no significant elec and mech activity. SI is still
Phase 2: Increasing action potential frequency - period of small disorganized contraction
Phase 3: Peak electrical and mech activity - large or intense contraction
Hormone responsible for peak electrical and mechanical activity of the mograting myoelectric complex
motilin
Secreted by the upper duodenum during fasting
motilin
it is the most important reflex
peristaltic reflex
gastrocolic and duedenocolic reflexes are transmitted by way of ____
ANS
Reflex contraction of the rectum and relaxation of the internal and external anal sphincter
defacation
Strongly inhibits the excitatory nerves and thereby causes intestinal paralysis, especially in patients with peritonitis
peritoneointestinal reflex
note: results from irritation of peritoneum
inhibit intestinal activity as a result of kidney irritation
renointestinal reflex
inhibit intestinal activity as a result of bladder irritation
vesicointestinal reflex
contraction of puborectalis muscle forms
anorectal angle
it maintains fecal continence
puborectalis muscle
In the pancreas, the digestive enzyme are secreted _______ and the large volumes of bicarbonate solution are secreted by the _________
- pancreatic acini
- small ductules and larger ducts leading to the acini
Pancreas secretes insulin and glucagon from where
Islets of langerhans
The liver secretes ____ which can be stored in the ______
- bile
- gallbladdes
What is the quantity of Bile production of the liver
600-1000 ml/day
what are the function of bile?
- emulsify fat particles
- aid in absorption of digested fats
what are the stages of bile secretion
- initial portion is secreted by the hepatocytes
- bile flows in the canaliculi -> interlobular septa -> terminal bile ducts -> larger ducts -> hepatic duct and common bile duct
What is the bile capacity of the Gallbladder?
30-60ml
What are the endocrine function of the pancreas?
insulin
glucagon
what are the exocrine functions of the pancreas?
enzyme lipase amylase protease bicarbonate
Pancreatic enzymes are used for?
Starch, protein, fat and DNA digestion
Pancreas secretion are inactivated but are activated by a ?
neural or basic pH blood supply
Secretions by this organ are quantitatively the largest contributors to enzymatic digestion of the meal
Pancreas
It attaches lipase to fat molecule
colipase
It prevents activation of trypsinogen to trypsin
PSTI (Pancreatic Secretory Trypsin Inhibitor)
Whys is PSTI (Pancreatic Secretory Trypsin Inhibitor) important?
Prevents pancreatitis (while trypsin is activated while in the pancreas)
A trypsin activator secreted by the intestinal mucosa when chyme comes in contact with mucosa
Enterokinase
___ are the most important enzymes in the pancreas for digesting protein
- trypsin
- chymotrypsin
- carboxypeptidase
note:
pancreatic amylase - digest carbohydrates
pancreatic lipases - digests fats
trypsin is the most abundant enzyme
It neutralizes the HCL acid emptied into the duodenum from the stomach
bicarbonate
Secretin is secreted by the ___
intestine (S Cells)
_____ stimulates the ductal cells of the pancreas to secrete/produce bicarbonate
secretin
Cholecystokin is secreted by the
intestine (I cell)
It stimulates the acinar cells of the pancreas leads to the secretion/production of pancreatic digestive enzyme
cholecystokinin
Factors regulating pancreatic secretion after a meal
Cephalic phase - stimulated by thought of food -> mediated by release of Ach and gastrin by vagal stimulation -> inc. secretion, with greater effect on enzyme output
Gastric phase - stimulus is protein in food -> mediated by gastrin -> inc. secretion with greater effect on enzyme output
- stimulated by gastric distention -> mediated by vago-vagal reflex -> inc. secretion with greater effect on enzyme output
Intestinal phase -
-stimulated by acid in chyme -> mediated by secretin secreted by duodenal S-cells -> inc. water and bicarbonate secretion
- stimulated by Long chain fatty acid -> mediated by cholecystokini and vago-cagal reflex -> inc. secretion with a greter effect on enzyme output
- stimulated by amino acids and peptides -> mediated by vago-vagal reflex and cholecystokinin -> inc. secretion with greater effect on enzyme output
What are the digestive function of the liver
release bile acids and bicarbonate
release bile acids and bicarbonate
Responsible for the feces’ yellowish or golden brown color
bile
what are the primary and secondary bile acids?
deoxycholic and lithocholic acid
chenodeoxycholic and cholic acid
primary: chenodeoxycholic and cholic acid
secondary: deoxycholic and lithocholic acid
