Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

GI Health > Esophagus and Stomach Physiology > Flashcards

Esophagus and Stomach Physiology Flashcards

(51 cards)

Start Studying
1
Q

Esophagus Outline

A

Muscular tube connecting mouth to stomach. Separated from pharynx by upper esophageal sphincter and from stomach by lower esophageal sphincter. 4 layers: mucosa, submucosa, lamia propria and serosa. Muscularis is thicker the normal for peristalisi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

3 phases of swallowing

A

mouth (voluntary), pharyngeal (involuntary) and esophagus (involuntary)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Oral Phase Outline

A

Voluntary. Stimulated by force applied to roof of mouth by bolus being pushed by tongue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Pharyngeal Phase Outline

A

Involuntary. Pressure in pharynx triggers receptor firing to swallowing center in brain (medulla and pons)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Pharyngeal Phase steps

A

closing of nasopharynx, closing of vocal cords, closing of UES, stopping of breathing, contracts pharyngeal constrictor (generates peristaltic wave) and food passes through esophagus to lower esophageal sphincter. Lower esophageal sphincter relaxes allowing bolus into stomach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Dysphagia Outline

A

Difficulty swallowing. Neurological (eg Parkinson’s), developmental (Downe’s syndrome) ,structural ( tumors) and psychological (phagophobia) disorders.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Dysphagia Complications

A

Malnutrition (nutrients can’t reach stomach) and respiratory problems (food enters trachea)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Dysphagia Outline

A

X-ray: barium solution coats esophagus, shows on x-ray. Endoscopy: put in esophagus to observe tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Dysphagia Treatment

A

Swallowing exercises, dietary changes (soft foods and liquids), feeding tubes (bypass swallowing), manometry (synthetically expanding throat by balloon expansion) and surgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Achalasia Outline

A

Degeneration of esophageal muscle and the nerves that supply them, results in difficulty for LES to relax. Results in difficulty swallowing and regurgitation of food (food never reaches stomach)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Achalasia Treatment

A

oral medication (eg Ca channel blockers), muscle relaxants (direct injection), manometry at LES and surgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Heartburn Outline

A

Acute backflow of stomach contents into esophagus due to LES inability to fully contract. Common occurs in everyone. Symptoms: burning in chest, cough and hoarsness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Gastroesophageal Reflux Disease (GERD/GORD) Outline

A

Chronic backflow of stomach’s contents into esophagus. Results in esophagitis and ulcers (progresses to Barett’s Esophagitis, and esophageal cancer)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

GORD Diagnosis

A

Barium x-ray, ambulatory acid (pH) probe and upper endoscopy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Gord Treatment

A

Medication: antacids, H2 antagonists, PPI (step up). Surgery: lix ring (exerts enough pressure to help LES close)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

4 anatomical regions of stomach

A

Cardia, Fundus, Body and Pylorus (antrum and pyloric canal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Cardia Function

A

Receives food from esophagus. Contains mucosal glands that secrete mucus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Fundus Function

A

Stores undigested food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Body Function

A

Where bulk of gastric digestion occurs. Biggest region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Pylorus Function

A

2 parts: antrum and the pyloric canal. Antrum opening of pyloric canal to the stomach’s body. Pyloric canal channels food to duodenum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

3 muscle layers in stomach (1 extra then esophagus)

Study These Flashcards
A

Circular (innermost), oblique, longitudinal (outermost)

22
Q

Gastric Mucosa Cells

Study These Flashcards
A

Surface mucus secreting, parietal cells, chief cells, enteroendocrine cells, enterochromaffin-like cells and nerve

23
Q

Surface secreting mucus cells

Study These Flashcards
A

Secrete mucus and HCO3^-. Protects stomach lining from abrasion and intense acid

24
Q

Parietal Cells Outline

Study These Flashcards
A

Produces HCl and intrinsic factor

25
Chief cells function
secrete pepsinogen and lipase
26
Enteroendocrine Cells
Secrete gastrin and somatostatin. Found mainly in antrum
27
Enterochromaffin-Like cells
Secrete histamine in response to gastrin. Found in lamina propria
28
Nerves in GIT Function
Effector and sensory nerves
29
Response to food entering and distending stomach (baroreceptors)
Acetylcholine release from enteric nervous system
30
Response to stomach registering food particles (chemoreceptors)
Gastrin release from G cells in body and antrum
31
Action of acetylcholine and gastrin
Either works directly on enteric cells (M3-Ach and CCKB-Gastrin receptors) or stimulates release of histamine from heterocroffin-like cells (M1-Ach and CCKB-Gastrin)
32
What happens with increased HCl concentration
D cells begin to produce somatostatin inhibiting G and parietal cells (forms negative feedback)
33
Response of Histamine, Ach and gastrin binding to receptors on parietal cells
Increase in cAMP and Ca^2+ production. Act as intracellular signalers. K+ and Cl- secretion begins
34
Response to K+ leaving cell
K+ binds to cell membrane receptor of K+-H+ ATPase pump activating transporter. K+ is pumped into cell and H+ is pumped out into lumen. H+ and Cl- combine outside of cell forming HCl which is released into stomach
35
Response to pH dropping (HCl conc increasing) in stomach
D cells produce somatostatin which inhibits cAMP aresponse to histamine
36
Intrinsic Factor Outline
Binds to Vitamin B12 in duodenum (after transcobalamin1 is degraded by pancreatic enzymes). This forms a complex that allows absorption through the epithelium (tubulin facilitated transporters). IF dissociates and trancobalamin 2 carries vitamin B to liver
37
Vitamin B12 Function in Body
DNA synthesis, red blood cell development, metabolism, neurotransmitter synthesis
38
B12 Deficency Symptoms
Anaemia, fatigue and lack of balance
39
Chief Cells Function
Secrete pepsinogen in response to Ach and gastrin levels
40
Pepsinogen as a zymogen
Not secreted in active form. It unfolds and undergoes autoclayses
41
3 protein digesting enzymes in GIT
pepsin (stomach), chymotrypsin (pancreas) and trypsin (pancreas)
42
2 main types of Gastric motility
Receptive relaxation and gastric contraction
43
Receptive Relaxation Outline
Vagally mediated reflex in fundus and body stimulated when bolus passes through esophagus (same time as LES relaxation), stomach wall relaxation. Stomach expands without significant pressure increase. Mediated as well by vasoactive intestinal peptide (VIP) and NO
44
Gastric Motility Outline
Driven by circular, oblique and longitudinal muscles. Maintained by basal electric rhythms generated by interstitial cells of Cajal (pacemakers). BER stimulates electrical depolarisation but can't induce contraction independent of hormones (Ach and Gastrin)
45
Gastric Motility Steps
Peristaltic contraction moves from fundus to pyloric sphincter (contraction becomes stronger as it approaches antrum). Chyme is pushed through LES (stronger contraction = more chyme). When peristaltic contraction reaches pyloric sphincter, sphincter closes (no further emptying). Chyme is pushed back into antrum and then propelled forward again by peristaltic wave (mixing)
46
Chyme movement in duodenum
~ 40 mins - few hours. Influencing factors: meal size, content (eg lipid, carbohydrate) and viscosity
47
Duodenum signaling for controlling gastric emptying
Duodenal distension (stretch receptors - enterogastric reflex), cholecytokinin and gastric inhibitory peptide responding to digestion products and secretin released in reponse to acid in duodenum (inhibits gastrin). These all inhibit/reduce gastric emptying. Allows duodenum to better process food
48
Gastroparesis Def
Stomach motility loss leading to blockages and stagnation. Treatment: change of diet/medication
49
Gastritis/ Peptic Ulcer Disease Def
Inflammation/ulceration of stomach wall due to loss of barrier function and mucosal exposure to acid. Treatment: acid inhibitors or antibiotics
50
Advantages of drug absorption in stomach
Cheapest, most convenient dosing method. Deviation between and within patients (food intake on the day and different rates of gastric emptying)
51
What substances can pass through lipid cell membrane
Lipophilic (non-ionised) drugs. Acidic

GI Health (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions