Sfos Exam 3

Front 1

Is the muscle in the oropharynx and upper 1/3 of esophagus smooth muscle or striated muscle?

Back 1

Striated

Front 2

Is the muscle is the lower 1/3 of the gut striated muscle or smooth muscle? What's the one exception?

Back 2

-Smooth muscle
-External anal sphincter is striated!

Front 3

What surface of the gut faces the lumen?

Back 3

Mucosa

Front 4

What are the 2 components of the extrinsic nervous system in the gut?

Back 4

Sympathetic and parasympathetic

Front 5

What is the 1 component of the intrinsic nervous system in the gut?

Back 5

Enteric nervous system

Front 6

What is the neurotransmitter that is used for the parasympathetic and sympathetic preganglionic fibers? What receptor?

Back 6

-Acetylcholine
-Nicitinic receptors

Front 7

What is the neurotransmitter that is used for the parasympathetic and sympathetic postganglionic fibers? What receptors?

Back 7

-Parasympathetic - acetylcholine in muscarinic receptors
-Sympathetic - norepinephrine in adrenergic receptors

Front 8

What are the 2 nerve plexi that make up the enteric nervous system? Where are they?

Back 8

-Myenteric in between the inner circular and outer longitudinal muscles of muscularis externae
-Submucosal is just deep to the submucosal layer (in between submucosal and inner circular muscle layer)

Front 9

Describe the vagovagal reflex.

Back 9

-Vagal afferent neurons
-DMX and Solitary Nucleus
-Vagal efferent neurons release Ach at nicotinic synapses.
(Eg stomach relaxes in response to distension in the esophagus)

Front 10

Is there digestion of carbs in the stomach?

Back 10

NO

Front 11

What is the rate limiting step of carbohydrate digestion?

Back 11

Transport into the enterocytes. ONLY monosaccarides.

Front 12

Where in the GI tract is most of the water absorbed?

Back 12

Duodenum and jejunum!

Front 13

Where is iron absorbed?

Back 13

Mostly in the small intestine. Through active transport via a specialized transporter

Front 14

Inhibitory or excitatory in the GI tract:
Substance P

Back 14

Excitatory

Front 15

Inhibitory or excitatory in the GI tract:
Neurokinin A

Back 15

Excitatory

Front 16

Inhibitory or excitatory in the GI tract:
Nitric oxide

Back 16

Inhibitory

Front 17

Inhibitory or excitatory in the GI tract:
Vasoactive intestinal polypeptide (VIP)

Back 17

Inhibitory

Front 18

What type of cell releases serotonin in response to stroking or stretch of the mucosa?

Back 18

Enterochromaffin cells

Front 19

Name the hormone:
"released in response to distension of the stomach or the presence of amino acids in the antrum (near the duodenum."

Back 19

Gastrin (from G cells in the stomah)

Front 20

Name the hormone:
"released in response to duodenal acidity, causes increased becarbonate secretion from pancreatic duct cells"

Back 20

Secretin (from S cells in the duodenum)

Front 21

Name the hormone:
"Released in response to fat and protein digestion products in the duodenum. Contracts gall bladder, increases exzyme secretion from pancreatic acinar cells"

Back 21

CCK aka cholecystokinin (from I cells in the duodunem)

Front 22

Name the hormone:
"Primes insulin release in response to antiipation of the nutrient absorption"

Back 22

GIP aka Glucose-dependent insulotropic peptide

Front 23

Name the hormone:
"involved in fasting contractions in the stomach and intestine"

Back 23

Motilin (from M cells in the lower stomach)

Front 24

Name the hormone:
increases bicoarbonate secretion from pancreatic duct cells". Increases intestinal secretion and inhibits smooth muscle contractility.

Back 24

VIP aka vasoactive intestinal polypeptide

Front 25

Name the hormone:
"released from cells in the ileum in responses to fat; slows motility (ileal brake)"

Back 25

Neurotensin and Polypeptide Y (PPY)

Front 26

Name the hormone:
"present in vagal terminals that innervate G cells (that secrete gastrin); increases gastrin release (stomach stretch, presence of aa's)

Back 26

GRP gastrin releasing peptide

Front 27

Serous or mucus secretion?
Parotid glands

Back 27

Serous

Front 28

Serous or mucus secretion?
Submandibular glands

Back 28

Both serous and mucus

Front 29

Serous or mucus secretion?
Sublingual glands

Back 29

Both serous and mucus

Front 30

Serous or mucus secretion?
Buccal glands

Back 30

Mucus

Front 31

Where does the ionic content of saliva get altered?

Back 31

In the salivay sucts AFTER being secreted by the acini

Front 32

Is salivation controlled by sympathetic pathways or parasympathetic?

Back 32

Parasympathetic

Front 33

How many primary teeth are there? How many secondary teeth are there?

Back 33

-20
-32

Front 34

Can you tell what blood type a person is by their saliva?

Back 34

YES!!!

Front 35

What is digested and/or absorbed in the esophagus?

Back 35

Nothing, the esophagus just passes food stuffs to the stomach

Front 36

What is the innervation of the esophagus? Consider both smooth and skeletal muscle.

Back 36

-Skeletal - vagus nerve directly to motor end plates
-Smooth - autonomics

Front 37

What stage of swallowing:
"Food pushed to posterior part of mouth; tongue forces food bolus into pharnx by pushing backward and upward against palate"

Back 37

Voluntary

Front 38

What stage of swallowing:
"Food stimulates swallowing receptor area; impulses sent to swallowing center in the brain stem"

Back 38

Pharyngeal stage (involuntary)

Front 39

Name 6 processes that occur during the pharyngeal stage of swallowing.

Back 39

-Soft palate pulled forward (closes posterior nares)
-Palatopharyngeal folds pulled medially (won't permit too-large bolus)
-Vocal cords close (protect airway
-Larynx pulled up and forward by muscles attached to hyoid (opens esophagus)
-UES relaxes and opens via chricopharyngeus
-Superior constrictor muscles of pharynx contract (starts peristaltic wave)

Front 40

What is the difference between primary peristalsis and secondary peristalsis during the esophageal stage of swallowing?

Back 40

-Primary - begins in pharynx and is initiated by a swallow. One wave for one swallow.
-Secondary - begins in the esophagus and is initiated by distention in the esophagus. Will continue until esophagus is empty

Front 41

What is described below:
"non-peristaltic (non-progressive), localized, segmental contractions of the esophagus"

Back 41

Tertiary contractions (ABNORMAL)

Front 42

What is the effect of rapid swallows on peristalsis in the esophagus?

Back 42

Delays peristalsis until swallowing is complete. "Clearing wave" after completion of swallowing

Front 43

What is it called when the LES relaxes with swallowing?

Back 43

"Receptive relaxation"
-Precedes peristaltic wave
-Maintained until peristaltic wave passes

Front 44

What effect does a hiatal hernia on reflux?

Back 44

-Reflux mostly related to a competent LES
-Reflux can be worsened by hiatal hernia in the setting of a hiatal hernia.

Front 45

Is the tonic contraction of the lower esophageal due to intrinsic muscle activity or to neural stimulation?

Back 45

Intrinsic muscle activity

Front 46

Is the relaxation of the lower esophageal sphincter due to an intrinsic property of the muscles or neural control?

Back 46

Neural stimulation of vagus nerve.
-Unknown neurotransmitter (NANC, possibly NO or VIP)

Front 47

Does a vagotomy affect the resting pressure of the lower esophageal sphincter?

Back 47

NO, tonic contraction is due to intrinsic muscle property.

Front 48

Does tetrodotoxini affect the resting tone of the lower esophageal sphincter or relaxation of the LES or both?

Back 48

Just relaxation (neurally controlled)

Front 49

Does these hormones increase or decrease LES pressure?
-Gastrin
-Motilin
-Substance P
-Pancreatic polypeptide
-Pitressin
-Angiotensin II

Back 49

Increased pressure

Front 50

Do the following substances increase or decrease LES pressure?
-Secretic
-Cholecystokinin
-Glucagon
-Gastric inhibitory polypeptide
-Vasoactive intestinal polypeptide
-Progesterone

Back 50

Decreased pressure

Front 51

What foods might decrease LES pressure?

Back 51

Fats
Alcohol
Chocolate

Front 52

What phase of swallowing?
"mastication and bolus formation"

Back 52

Oral preparatory phase

Front 53

What phase of swallowing?
"transport bolus to the posterior area of the oral cavity"

Back 53

Oral phase

Front 54

What is the most effective mechanism to prevent aspiration during swallowing?

Back 54

Adduction of the true vocal cords

Front 55

What with dysphagia would you use thin fluids? Thick fluids?

Back 55

Thin fluids - poor clearance but no aspiration
Thick fluids - aspiration

Front 56

What cell type is described:
"May contribute to cell defense; has lysozymes stored in granules; can also phagocytose"

Back 56

Paneth cell

Front 57

What cells secrete HCl?

Back 57

Parietal cells

Front 58

Where in the stomach are parietal cells (oxyntic) located?

Back 58

Cardia, fundus, corpus

Front 59

What cells secrete intrinsic factor?

Back 59

Parietal cells

Front 60

What is the function of intrinsic factor?

Back 60

Necessary for the absorption of Vit B12 in the ileum

Front 61

What are 3 examples of enteroendocrine cells?

Back 61

-G cells secrete gastrin
-S cells secrete secretin
-M cells secrete motilin

Front 62

What is the function of somatostatin?

Back 62

Inhibits the release of gastrointestinal hormones

Front 63

What are SGLT's and why are they important?

Back 63

-Sodium-dependent glucose transporters
-These proteins use the energy from a downhill sodium gradient to transport glucose across the apical membrane against an uphill glucose gradient.

Front 64

What two cell populations are found in the myenteric plexus?

Back 64

-Post-ganglionic parasympathetics
-Neurons of enteric nervous system

Front 65

Is there a basal electrical rhythm in the esophagus?

Back 65

NO, not in the esophagus, the proximal stomach, or the sphincters

Front 66

Is there a basal electricla rhythm in the colon?

Back 66

Yes, in the colon, the small intestines, and the distal stomach

Front 67

Can action potentials occur in the gut without any extracellular Ca2+?

Back 67

No

Front 68

Do the following factors increase or decrease excitability in the bowels:
"stretch, ACh, parasympathetics, GI hormones, Substance P"

Back 68

Increase excitability (move towards depolarization)

Front 69

Do the following factors increase or decrease excitability in the bowels:
"Norepinephrine, Epinephrine, NO, Vasoactive intestinal polypeptide, sympathetics"

Back 69

Decrease excitability (move towards hyperpolarization)

Front 70

What do the pelvic splanchnics innervate in the GI tract?

Back 70

Parasympathetic innervation to the hindgut

Front 71

What does the vagus innervate in the GI tract?

Back 71

Parasympathetic innervation to the esophagus, stomach, pancreas, intestine

Front 72

What are the 2 excitatory ENS neurotransmitters?

Back 72

Ach and Substance P

Front 73

What are the 2 inhibitory ENS neurotransmitters?

Back 73

VIP and NO

Front 74

What is the function of the interstitial cells of Cajal?

Back 74

Pacemaker cells of the GI tract

Front 75

What is an example of a short reflex in the gut?

Back 75

The control of peristalsis and mixing in the gut. Requires the coordination of the inner circular muscle and the outer longitudinal muscle coordinated by the ENS.

Front 76

What is an example of a long reflex in the gut (but not including the CNS)?

Back 76

The gastrocolic reflex

Front 77

What is an example of the longest reflex in the gut (involving the CNS)?

Back 77

The vagovagal reflex involving receptive relaxation of the stomach in response to the swallowing of food.

Front 78

Is there MMC (migrating motor complex) in the colon?

Back 78

No, only in the stomach and small intestine

Front 79

What is gastroparesis?

Back 79

Delayed gastric emptying

Front 80

What ions come in to depolarize the smooth muscle in the gut when action potentials are generated?

Back 80

Ca2+ and Na+

Front 81

Is the enterogastric reflex a short, long, or longest reflex?

Back 81

Long

Front 82

What effect does eating have on the MMC (Migrating motor complex)?

Back 82

Stops it!

Front 83

What do chief cells of the stomach do? Where are they found?

Back 83

-Releases pepsinogen
-Mostly in the fundus of the stomach

Front 84

Is the vagus N primarily afferent or efferent in dealing with the gut?

Back 84

Primarily afferent

Front 85

What vagus nucleus controls striated muscle of the esophagus?

Back 85

Nucleus ambiguous

Front 86

What vagus nucleus controls smooth muscle of the esophagus?

Back 86

Dorsal motor nucleus (DMX)

Front 87

What is the enterogastric reflex?

Back 87

It delays gastric emptying

Front 88

Where are Paneth cells found?

Back 88

Small intestine- they are thought to be part of the host defense system

Front 89

Where do you find lacteals?

Back 89

In the lamina propria of villi in the small intestine

Front 90

What is the function of Brunner's glands?

Back 90

-Secrete mucus in response to vagal stimulation and tactile stimulation
-Protects the duodenum from acid coming from the stomach.

Front 91

What is the basic process of digestion of carbs, proteins, and fats?

Back 91

Hydrolysis! Accomplished by different enzymes for different food stuffs.

Front 92

What are the 3 basic monosaccarides that an enterocyte can absorb? Where does this occur?

Back 92

-Glucose, fructore, galactose
-Throughout small intestine primarily JEJUNUM

Front 93

What's special about the absorption of Vit B12? Where does absorption occur?

Back 93

-Requires intrinsic factor secreted by the parietal cells in the stomach.
-Absorbed in the ileum

Front 94

Is the parotid gland serous or mucus secretions? Is the pancreas serous or mucus secretions?

Back 94

Both are ONLY serous.
BUT:
-parotid gland has fat cells
-pancreas has centroacinar cells

Front 95

What effect does fat in the ileum have on gut motility?

Back 95

Decreases gut motility (ileal brake)

Front 96

Does exercise, NG tubes, or laxitives help resolve an ileus?

Back 96

NO!