Physiology of oral cavity and esophagus T. Smith

Question 1

The act of swallowing pushes food down the esophagus, disposes of (blank), opens (blank), and stops (blank).

Answer 1

mucus (bacteria and dust)
Eustachian auditory tube
breathing

Question 2

What is deglutination?

Answer 2

swallowing

Question 3

The cripharyngeal muscle is always (blank). When a bolus of food comes, this muscle must be (blank)>

Answer 3

constricted, relaxed

Question 4

What muscles must constrict to aid food through the esophagus? These and the cripharyngeal muscle make up what?

Answer 4

superior pharyngeal constrictor muscle
middle pharyngeal constrictor muscle
inferior pharyngeal constrictor muscle
they make up the upper esophageal sphincter

Question 5

Integrated neural pathways mediate (blank).

Answer 5

swallowing reflex

Question 6

Where are the swallowing centers located? What do they do?

Answer 6

in the medulla

controls muscle relaxation and contraction

Question 7

What are the major peripheral sensory inputs to the swallowing center carried by?

Answer 7

1)the maxillary branch of the trigeminal nerve (V2)
[face, sinus and teeth]
2)the glossopharyngeal nerve (IX) [Posterior 1/3 of tongue, tonsil, pharynx and middle ear]
3) the superior laryngeal branch of the vagus (X) [larynx, pharynx].

Question 8

The motor output of the swallowing center is via the motor branches of the????

Answer 8

trigeminal (V) [muscles of mastication]
facial (VII) [muscles of face]
glossopharyngeal (IX) [stylopharyngeous, upper pharyngeal muscles]
vagus (X) [palate, pharynx, larynx, esophagus]
and
hypoglossal (XII) [tongue muscles].

Question 9

(blank) is the symptom of the failure of normal propulsion of the bolus from mouth to esophagus. Because the oropharyngeal phase of swallowing is coordinated with respiratory activity, respiratory symptoms often accompany

Answer 9

oropharyngeal dysphagia

Question 10

Oropharyngeal dysphagia and associated respiratory symptoms are caused by:

Answer 10

1) a failure of the driving force
2) obstruction to flow
3) a combination of 1 and 2

Question 11

(blank) is an autoimmune neuromuscular disease leading to fluctuating muscle weakness and fatigability. It is an autoimmune disorder, in which weakness is caused by circulating antibodies that block acetylcholine receptors at the postsynaptic neuromuscular junction, inhibiting the excitatory effects of the neurotransmitter acetylcholine (Ach) on nicotinic receptors throughout neuromuscular junctions.

Answer 11

myasthenia gravis

Question 12

(blank) is a motor neuron disorder that can lead to swallowing difficulties.

Answer 12

poliomyelitis

Question 13

(blank) is a muscle disease characterized by inflammation and a skin rash. It is a type of inflammatory myopathy. It is one of a group of acquired muscle diseases called inflammatory myopathies. Problems with swallowing (dysphagia) may occur.

Answer 13

dermatomyositis

Question 14

What can these cause:
Cerebral vascular accident
Poliomyelitis
Myasthenia gravis
Dermatomyositis

Tumor or abscess
Cricopharyngeal achalasia

Answer 14

Oropharyngeal dysphagia

Question 15

primary peristalsis is triggered by (Blank)

Answer 15

swallowing

Question 16

THe pressure wave that moves down the esophagus during swallowing is coordinated with opening of the (blank) which relaxes before the propagating contraction. (i.e it relaxes first then contracts after)

Answer 16

Lower esophageal sphincter

Question 17

Where is there a delay during swallowing?

Answer 17

in the smooth muscle parts of the esophagus

Question 18

What part of the esophagus has the highest pressure?

Answer 18

the Upper esophageal sphincter

Question 19

Swallowing or a bolus of food in the pharynx stimulates tension receptors in the wall of the pharynx. Pharyngeal contraction coincides with relaxation of the (Blank) and relaxation of the (Blank). This remains relaxed until the (blank) arrives which consists of sequential phasic contraction along the esophageal body, which propels the swallowed bolus toward the stomach.

Answer 19

Upper esophageal sphincter
lower esophageal sphincter
peristaltic wave

Question 20

When food goes down the esophagus what does the muscle do?

Answer 20

the longitudinal muscle shortens and the circular muscle constricts

Question 21

What are the thre major layers of the esophagus?

Answer 21

mucosa and submucosa
circular muscle
longitudinal muscle

Question 22

What is the nerve plexus between the longitudinal muscle and the circular muscle called?

Answer 22

the myenteric plexus

Question 23

What muscle type does polymyositis and myasthenia gravis attack in the esophagus?

Answer 23

striated

Question 24

What muscle type does scleroderma and achalasia attack in the esophagus?

Answer 24

smooth

Question 25

The proximal portion of the esophageal body is composed of striated muscle and is innervated by somatic lower motor neurons whose cell bodies are located in the (blank)

Answer 25

nucleus ambiguous (NA).

Question 26

The more distal portion of the esophageal body is composed of smooth muscle and is innervated by (blank) fibers whose cell bodies are located in the (blank) and synapse with intramural neurons whose cell bodies are located in the (Blank) of the esophagus.

Answer 26

vagal preganglionic dorsal motor nucleus (DMN) myenteric plexus

Question 27

What nerve creates persistaltic contractions in the esophagus?

Answer 27

vagus!

Question 28

Vagus nerves arising from the Nucleus Ambiguous release (blank) directly onto the skeletal muscle where they activate (blank) on Skeletal Muscle Fibers to produce contraction.

Answer 28

Ach | Nicotinic receptors

Question 29

Vagus nerves arising from the DMN release (blank) where they activate (blank) on (blank) inhibitory and excitatory motor neurons to the smooth muscle to produce relaxation followed by contraction.

Answer 29

Ach Nicotinic receptors myenteric

Question 30

What is the resting pressure of the esophagus everywhere other than the LES or UES?

Answer 30

zero or slightly negative

Question 31

What has a prolonged relaxation the UES or LES?

Answer 31

LES

Question 32

When the vagus nerve is causing relaxation what is released?

Answer 32

NO/ VIP

Question 33

Latency of esophageal contractions is regulated by (blank)

Answer 33

Nitric oxide

Question 34

If you treat the smooth muscle of the esophagus with a inhibitor of NO, what happens?

Answer 34

you lose the latency gradient of contraction (i.e. you dont have delayed contractions)

Question 35

If you treat smooth muscle of the esophagus with a muscarinic inhibitor, what happens?

Answer 35

have very small contractions :(

Question 36

WHat 2 things make up the intrinsic and extrinsic sphincters. The two structures are superimposed and anchored by the (blank) ligament.

Answer 36

LES and crural diaphragm | phrenoesophageal ligament

Question 37

Esophageal peristalsis is initiated in what 2 ways?

Answer 37

swallowing (primary peristalsis) and esophageal distention (secondary peristalsis)

Question 38

(blank) is triggered by distention in the smooth muscle portion of the esophagus. Contraction orad (nearer to the mouth) to the bolus is followed by a descending pressure wave that is coordinated with lower esophageal sphincter opening.

Answer 38

secondary peristalsis

Question 39

This is the control of peristalsis by the (blank) Peristalsis can be triggered when a sensory nerve detects distension or luminal acidity. Interneurons convey the signal to excitatory and inhibitory nerves above and below the site of stimulation, respectively. ACh, acetylcholine; NO, nitric oxide; VIP, vasoactive intestinal polypeptide

Answer 39

enteric nervous system

Question 40

Ascending interneurons activate (blank) Motor Neurons that release acetylcholine (Ach) that excite muscarinic receptors on the smooth muscle leading to contraction of the smooth muscle above the bolus. Whereas descending interneurons activate (blank) Motor Neurons that release nitric oxide (NO) and vasoactive inhibitory polypeptide (VIP) onto the smooth muscle to cause relaxation of the smooth muscle below the bolus respectively.

Answer 40

Excitatory | Inhibitory

Question 41

LES relaxation is (Blank)

Answer 41

neurogenic

Question 42

These do something to LES: (blank) stimulation relaxes it it is blocked by (blank) it is blocked by (blank)

Answer 42

vagal tetrodotoxin (TTX) Hexamethonium

Question 43

(blank) is the inhibitory neurotransmitter that mediates esophageal relaxation.

Answer 43

Nitric oxide

Question 44

What do anticholinergic drugs do to LES pressure in man?

Answer 44

decreases it

Question 45

If you block nicotine what happens to the LES?

Answer 45

it doesnt relax or contract properly

Question 46

What three factors play a role in determining resting LES pressure?

Answer 46

Neurogenic - cholinergic blockade decreases sphincter tone. Myogenic - vagotomy or cholinergic blockade does not lead to total abolition of sphincter tone 3) Hormonal - the differing effects on LES pressure by fat and protein meals is best explained by hormonal action.

Question 47

What is this: Failure of propulsive force Obstruction to flow In-coordination of contraction and relaxation

Answer 47

dysphagia

Question 48

What are three symptoms of esophageal dysfunction?

Answer 48

gatroesophageal reflux systems dysphagia esophageal pain (non cardiac chest pain)

Question 49

(blank) involves inserting a long, flexible tube (endoscope) down your throat and into your esophagus. A tiny camera on the end of the endoscope lets a gastroenterologist examine your esophagus, stomach and the beginning of your small intestine (duodenum).

Answer 49

upper endoscopy procedure

Question 50

If you have myasthenia gravis what happens to your UES? How do you treat this?

Answer 50

you cant get it to relax | give an anticholineresterase :) (it prevents break down of acetylcholine)

Question 51

What is edrophonium?

Answer 51

an anticholineresterase

Question 52

The heart and the esophagus are located in the chest cavity (thorax) in close proximity. SOO They receive very similar (blank) supply. Thus, pain arising from either organ travel through the same nerve sensory fibers to the brain. What does this mean for us!?!?

Answer 52

nerve pain from either organ may have similiar presentations of pain so it can be hard to differentiate where the pain is coming from.

Question 53

(blank) is a condition in which the stomach contents (food or liquid) leak backwards from the stomach into the esophagus (the tube from the mouth to the stomach). This action can irritate the esophagus, causing heartburn and other symptoms.

Answer 53

GERD

Question 54

(blank) is a change in the normal lining of the esophagus (squamous mucosa) to a lining similar to the lining of the stomach (columnar mucosa) that is visible by endoscopy.

Answer 54

Barrett's esophagus

Question 55

(blank) occurs when part of your stomach pushes upward through your diaphragm.

Answer 55

hiatal hernia

Question 56

Name the procedure and what it is for? In this procedure, the surgeon wraps the top of the stomach around the lower esophagus. This reinforces the lower esophageal sphincter, making it less likely that acid will back up in the esophagus.

Answer 56

The Nissen Fundoplication for GERD

Question 57

(blank) is a disorder of the movement of the esophagus. It causes difficulty swallowing, or dysphagia, to both solid and liquid foods, and can cause chest pain; it may also be asymptomatic. It is a disorder with very intense contractions of the esophagus!

Answer 57

Nutcracker esophagus

Question 58

(blank) is a disease where the LES cannot relax due to a loss of inhibitory neurons, or a loss of both inhibitory and excitory neurons resulting in loss of contraction and relaxation.

Answer 58

achalasia